Click subject below for report ▼
ANIMALS
with
Paul Reeves
BIRD BOX
with
Paul Reeves
BOWL
from a BLANK
with
Paul Reeves
BOWL TURNING TECHNIQUES
with
Paul Reeves
BOX of CONTRASTING WOODS
with Paul Reeves
BUTTONS
with Paul Reeves
COLOURING with a
SPLASH
with Paul Reeves
GAVEL
with Paul Reeves
HANDLES & FEET
with Graham Turner
JEWELLERY
with
Andy Ogilvie
and Paul Reeves
KILNER JARS
with
Andy Ogilvie
KITCHEN ITEMS
with
Paul Reeves
LIGHT BULBS in wood
with
Paul Reeves
MIXED SOLID MEDIA with
Andy
Ogilvie
MUSHROOMS DECORATED
with
Paul Reeves
OFF-CENTRE
TURNING
with
Paul Reeves
OFF-SET BOWLS
with
Paul Reeves
PLATES &
PLATTERS
with
Paul Reeves
PLYWOOD
with
Ed Walker
PODLETS
with
John Bolt
PUZZLES & TRICKS
with
Paul Reeves
SPHERE TURNING
with Paul Reeves
SPINDLE & FACE PLATE TURNED
with
Paul Reeves
SPINDLE revision
with
Paul Reeves
STRAIGHT
from the TOOL
with
Paul Reeves
STREPTOHEDRONS
with
Andy Ogilvie
THREAD CUTTING SCREW BOX & TAP
with
Paul Reeves
THREE POINT
BOWL
with Andy Ogilvie
TEXTURING
with
Paul Reeves
THREE LEGGED STOOL
with
Paul Reeves
TOOTHPICK HOLDER
with
Paul Reeves
TOY CAR RACING
with
Andy Ogilvie
TWO-PART
STICK/LAMP + ADDED VALUE
with
Paul Reeves
UNNATURAL NATURAL EDGE
with
Paul Reeves
Click subject above for report ▲
August 2024 DEMO
3
Straight
from
Tool turned pieces with
Paul
Reeves
Thu 15th August at MWCC Club Night
Straight from the Tool is a technique that
provides the best possible turned surface without requiring any use of
abrasives. To perfect this, takes time & skill.
Indeed, it wasn't until the 13th century before sandpaper was
invented in China and before then, any wood turning had to be left as tool
finished with the possible exception of refinement using wood shavings and (in a few parts of the
globe) fish skins.
Trying to complete a turned piece "straight from
the tool" shows up one's Tool Control, Tool Sharpness & Lathe's performance in
absolute clarity.
Control relies upon practice & experience of getting the bevel
position correct;
Sharpness comes with recognizing when a cutting edge needs attention;
Performance deteriorates from adverse vibrations caused by worn bearings of
headstock drive centres and/or tailstock centres or even a lumpy toolrest while
moving one's gouge along it.
Some turners have no alternative to turning this way - for example,
the fascination of Pole
Lathe turning is the hand-made look of natural tool finish;
Ornamental Lathe
turning relies upon intricate sharp-edged decorated pieces that would be ruined
by sanding.
How many of us take time to just practice using our gouges to achieve a smooth
finish, particularly with a 'difficult' wood to work, eg Paraná Pine? You
will quickly discover
that you need to select the right wood for the project,
that sharp tool edges are essential and
that high lathe speed is often your friend.
Spindle Work
Along Grain :
Paul had a piece of Paraná Pine mounted between centres and knocked the corners
off with a Roughing Gouge presented at right angles in the first instance to produce a
cylinder with a dull finished surface. This surface was improved by
presenting the same gouge angled at about 45º from vertical with the bevel
smoothing off the freshly cut surface as it moved along the tool rest. An even
better finish is with a Skew Chisel achieved by raising the toolrest so that
only the lower third of the tool is in contact with the upper quadrant of the
piece, which avoided adverse twisting of the tool in your hand and sliding
off the rest. The German Christmas Decoration turners of Seiffen use a square
ended tool but angled Skews are invariably used by us. These Skews have cutting
edges angled either straight or curved in an arc. The curved type have the
advantage of finer control by easily adjusting the cutting point by up/down
movements of the handle but the more acute the angled edge cuts the surface, the
more difficult it is to stop the cut moving in/out creating ripples so it does
demand very steady hand movements. The straight angled Skew is more stable for
the occasional Skew user.
Top Tip
: if using
any angled Skew, use the edge with the shorter side resting on the toolrest - or
in other words, with the acute angled corner uppermost. Move with your
body rocking on your legs rather than moving hands with your arms.
The Skew finish can look and feel like you've sanded down to 800 grit and
frankly, any use of abrasive is likely to be detrimental.
Cross Grain : Paul demonstrated different tools one could use.
①
His ¼" Beading & Parting Tool was shocking at cutting across grain causing
multiple pull-outs;
② His thin tipped Parting Tool
had less contact damage which was fine with close grain woods;
③ His Skew had the best finish
provided he only cut tiny slithers (about ¼mm)
successively but this time with the longer side resting on the toolrest (i.e. sharper
angled corner lowermost).
Beads and Coves are also cutting across the grain of spindle work and require a recently sharpened Spindle Gouge to cut from larger diameter to smaller. These procedures were previously described back in May 2024 and can be found in 'Spindle Revision' < here >
Bowl Work
As the walls of a bowl comprise of a
combination of along/side grain and across/end grain wood, fresh cut blanks will distort
as they dry out.
It is essential for the dried blank to be held solidly in your chuck jaws when
you are ready to finish it, so some thought should be put into how to rough your
bowl in preparation.
Bowl blanks are best roughed out to a wall thickness about 10% of the overall diameter as this is
average shrinkage amount around the annual rings and leaves plenty of room to
true up later. Some woods eg Alder, Yew hardly move at all whereas Cherry (as
you can see from the picture below) moves a lot during shrinkage when the wood
also warps in two directions; i.e. the opposite sides
that are along grain will shrink closer together and to a lower height than the
across grain sides.
Paul anticipates this by roughing the blank so that the spigot on the bottom is
finished with a pop mark in its centre and pencils the date on the bowl's lip.
If the roughed out bowl is either wide or shallow enough for a chuck key to
operate, he additionally creates a dovetail spigot inside the bowl bottom
together with a pop mark there too. Note
that some chuck keys have hexagonal ball ends that can still adjust the jaws at
oblique angles.
Once dried out many months later, the outside
spigot will be oval and will need to be re-trimmed circular, ideally to the
'True Circle' jaw diameter in order to be held rigid even if the spigot is only
a few millimetres proud.
This can be achieved by :-
either driving the piece between a Jam Chuck acting against the inside of
the bowl and a tailstock centre pressing into the pop mark,
or if applicable, with a chuck gripping the prepared inside dovetail and with a tailstock on
the pop mark.
Outer Surface
Paul's Walnut rough blank did have an internal dovetail - but first, he gripped
the outside oval spigot as best he could with the inside supported by the tail
stock in order to level off the lip of the bowl.
Then with the piece remounted with long-reach or o'Donnell jaws to the inside
dovetail together with a tailstock to the base pop mark, he re-trimmed the base
spigot to true circle as described above.
While mounted in this position, he applied pull cuts from the centre to about
halfway up the side; if he had continued any further, he would be dragging the
tip over wood that was rapidly changing from side grain to end grain twice every
revolution, which would end up rough - particularly with hard dried out wood.
In order to give a better surface cut, one can change the pull into a push cut
by moving the tool handle from in front of to behind the tip in one deft
manoeuvre such that the bevel will now smooth the cut onwards to the lip of the
bowl.
Unfortunately, this Walnut bowl was so hard in places that it was difficult for
Paul's gouge not to be kicked about uncontrollably. There were 3 likely
explanations :-
1. Combination of the lathe speed & the gouge were moving too quickly;
2. Pushing too hard down on the gouge;
3. Cutting tip was above centre and the hard parts of the grain were
ending up bouncing against the bevel resulting in only the softer wood getting
cut away leaving the hard pieces getting relatively higher, aggravating the
fault.
Incidentally, if one resorted to abrasives at this stage, it would compound the
situation because more would be lost off the softer along/side grain than the
denser across/end grain resulting in a change of bowl shape. In Paul's
Walnut bowl piece, this was further accentuated as the sides were sapwood and
the ends were heartwood.
The solution is to carefully cut away the hard parts in tiny amounts on each
pass. All other methods (e.g. scrapers) are likely to result in pull outs.
Sharpening
your gouge or changing to a smaller tipped gouge can help.
To remove tool marks, a useful ploy is to use the lower wing of a Bowl Gouge to
gently dress the surface with a slight shearing angle. Be careful to
ensure the top wing does not touch the piece with this method. Many
of us sharpen gouges with a 'fingernail' profile whereas a straight edge wing
profile is better for this job.
Sanding Sealer (quite acceptable for tool finish pieces) will help to stand up
the wood fibres making it easier to cut them off.
Top Tip
: Although the wood fibres are now standing proud, they are all
still bent over in one direction. If your lathe is capable, when getting to your
finishing cut, try reversing the direction of turn and with the tool rest and
gouge/shear scraper positioned to the far side, you will now be cutting from
underneath the raised fibres, resulting in a much smoother finish. This is the
same reason that changing direction of turn with abrasives is so effective.
This will work for both inside & outside surfaces. NB Beware that heavy
contact could start to unscrew the chuck from the head stock.
After applying Sanding Sealer with brush or
cloth, pressing paper with lathe turning created heat to help dry the sealer
off. Now when you pass your gouge over the piece, wherever the surface is low,
the untouched Sealer shows up as still shiny.
One also needs to consider whether the surface you are working will be in
contact with food, in which case use water instead of Sanding Sealer to stand
the fibres up.
Inner Surface
With the piece remounted on the base spigot, Paul
quickly removed the inside spigot in order to be able to make one continuous
pass for the following cuts. Whenever one stops a cut and restarts again,
it is inevitable that a witness line will be left on the surface.
One remedy is to use a curved surface tool. Although it is better to cut
rather than scrape, smooth movements, for example, with a Negative Rake Scraper
can provide the finest surface finish. However, the drawback is the edge doesn't
last very long and needs regular tickling with the diamond file whenever the
shavings become irregular. Reapplying Sanding Sealer often helps when you are
near the final passes.
The correct use of a scraper is to position the toolrest so that the tool is
slightly handle high with the cutting edge at the 9 o'clock position. If your
Scraper (e.g. Taylor Teardrop Cutter) has a round bar sitting on the tool rest,
one can avoid the tendency of the end grain parts of the piece from being
levered up by twisting the tool anticlockwise such that the scraper edge is at
an angle, which will help to slice the surface.
Now it is just patience and care to
remove all the tool marks as best that you can by trying to reach the same
colour without the Sanding Sealer highlighting any lows.
Paul finished with shaping the rim and its inside edge with his Negative Rake
Scraper while carefully supporting the outside surface with his fingertips.
The September 2024 Competition was set to turn piece(s) without any sanding - although oil/sealer finishes are acceptable
(photos by Rick
Patrick & Andy Ogilvie)
<to
top>
June 2024
DEMO 2
Mixed Solid Media with
Andy
Ogilvie
Thu 20th June at MWCC Club Night
SOLID MEDIA refers to different materials that
can be worked.
These include :
wood
soft metal
epoxy resin
acrylic
Perspex
Corian
Milliput epoxy putty
etc
A piece of wood with just paint, pyrography or made out of 2 or more different types of wood doesn't
strictly satisfy the
criteria of
MIXED SOLID MEDIA,
whereas, two or more combinations of the above examples does, whether used within the
body of the piece, or as a decoration.
For example, Andy had used
Perspex as a lid to his wooden kitchen Salt Pot to
keep moisture out while able to see what was in that particular pot;
turned
Corian to enhance an opening;
napkin rings decorated with Milliput;
a Laburnum
urn decorated with brass rivets.
(click for close up view)
(click for close up view)
In précis, Mixed Solid Media pieces
can be :-
♦ COMBINATIONS of the above media or kits (egg timers, clocks, pens etc);
♦ DECORATIONS of solid media applied to a piece;
♦ INTEGRATED MATERIALS which form a blank for subsequent turning.
This demonstration will give more
detail of how to achieve some of the above processes.
Andy warned that using open-grained wood had difficulty in maintaining a sharp
edge between wood and putty/metal alloy once the piece had been sanded back to a
smooth finish, because the slurry had a tendency to penetrate into the wood
grain resulting in a cloudy grey effect near the joint between the media.
For his demonstration, he had chosen Boxwood.
Andy's basic message was, "Don't be put off with experimenting with these
various materials just because they are unfamiliar. They are all manageable."
Milliput Epoxy Putty
Milliput comes in 2-pack blocks of putty in black, yellow grey, silver grey,
terracotta and superfine white, (the latter can be used for creating very fine
details). In preparation for applying his Milliput around the body of his
box, Andy used a Parting Tool to create a recess about 3-4mm deep and about 5mm
wide, although he deliberately countersunk the sides to be wider at the bottom
of the recess in order to help secure the putty in position once cured. After
cleaning the surfaces, he applied a coat of sanding sealer which would help
keeping the wood clean with a simple wipe.
When new, the putty is malleable
although it will be less so with age after opening.
Top Tip
: If putty has become stiff
with age, try working each block separately while under the stream of warm air
from a hairdryer but be aware that heating reduces the curing time and hence
less time to manoeuvre into situ. Adding a
little water can also soften the paste.
Having selected equal quantities of both parts, Andy mixed them well together before rolling out into a thin sausage and pressed into the recess while aiming to minimise gaps/holes. There was no need to skimp on the amount used because it cleans off easily and used for the next recess. Andy often uses different width of recesses to create interest.
Depending upon temperature and age of putty, it would take about 2 - 3 hours for the Milliput to 'cook' and harden off enough before one could turn the piece with a gouge or sand back. Milliput can be readily shaped by gouge and particularly receptive to sanding.
Andy also described other effects that could be produced using different coloured putty like the black and white chequered feature shown below.
Soft Metal
Andy had brought along some "Wood's Metal" bars of bismuth/lead/tin/cadmium alloy which have a
surprising low melting temperature of 70ºC (not much hotter than solder) and
would melt in a spoon with a hot air gun, particularly when the
alloy bar is cut into tiny pieces. He warned against using solder as it
tended to be difficult to pour without solidifying before it filled up all the
space and it doesn't polish up as well as the alloy. Pewter is a suitable
alternative but requires higher temperature to become molten.
As we are relying upon gravity to help us, trying to cast a metal ring around
the side of the box is a difficult process. However, flat surfaces like a box
lid are perfect.
So while the lid section of his box was still connected to its body on the
lathe, he prepared as he had done for the putty by forming a countersunk recess into the end of the piece but then added a slight bevel to
the edges of the recess; these bevels encourage the molten alloy to fall into
the recess.
After cleaning the surfaces, he again treated with a coat of sanding sealer.
With the lid now set flat, the chips of alloy were placed in a spoon and heated with a hot air gun until molten about 45 seconds later when it was poured into the recess. Enough alloy was dropped in for the meniscus to just bulge above the prepared bevel. This was to allow for any dipping as the alloy cooled & solidified. Dependent upon the volume of alloy used, it should be ready to work within 10 to 30 minutes. The aim was to minimise wastage and to have very little to turn away with a gouge. Before any sanding, another coat of sanding sealer was applied and subsequent abrasives were carefully used lightly with fine grits only & at a slow speed to avoid frictional heat re-melting the alloy.
Integrated Resin
A quick Google search for "resin for beginners kit" will show there are many
suppliers out there, which might seem daunting but can be rewarding with a
little perseverance. There are 3 types of resin; Epoxy, Polyester &
Polyurethane but epoxy is best for gaining experience. Many starting sets
are for thin projects but woodturning
projects tend to require several centimetres thickness, which you will need to
consider before buying.
They all require mixing of the resin with a hardener. The deeper the
cure mixture, the more that stirring and higher curing temperature can create
bubbles which would detract from the finished article. To overcome this problem,
some suppliers sell specific epoxies & hardeners for different depths while some
guide you to different ratios of resin to hardener. Others explain how to remove
bubbles using heat guns or even toothpicks! One method includes using
pressure pots that will compress air bubbles to sizes so small that you will not
be able to see them, in order to achieve a high quality clear casting at the
cost of several hundreds of pounds Sterling!
Not surprisingly, the duration of the curing process is variable from maybe 10 -
24 hours so it is always best to leave the turning for at least a day.
"How to make a combination of wood and resin blank for
turning" is best done by asking Google that very phrase and watching one
of their helpful videos.
The basis is :
Prepping the mould with the wood;
Put in some means for the chuck jaws or screw chuck to grip;
Tape the wood down so that it doesn't float away when the resin is poured in;
Mix the resin and hardener;
Stir in colour/sparkle as desired before pouring;
and leave for at least 24 hours.
Next day, you should have something like Andy's photo above; the Polyfilla tub acted as the mould and he has already used the lathe to create a new spigot for the base of the bowl whilst mounted in the jaws using the wooden spigot partially buried in the resin. Andy had found that warming up the hardener/catalyst seemed to help it mix with the resin more efficiently and he advocated leaving the mix still for 15 mins to give bubbles a chance to dissipate. He had added a blue tint and some sparkles.
Much of the initial sanding of the resin piece was with a 50mm padded drill attachment but after fine abrasives and spray lacquer to finish, it looked like this ...
The July 2024 Competition was set to turn any piece of combination, decorative or integrated styles that incorporates two or more Mixed Solid Media
A
Cautionary Tale - Having seen some bamboo
stalks encased in resin on You-Tube, Andy told of his attempt to incorporate
this idea into one of his projects. To the left, you can see the pot
within which he had arranged a circle of bamboo to be set in some resin, somewhat
mimicking an orange. After allowing to cure and fitted into a chuck, Andy
experienced a catastrophic failure when upon starting the lathe, the resin
failed to hold the whole piece together and the orange suddenly broke up into 'segments'. You might spot in the photograph that some significantly large
pieces detached themselves and indeed there is one piece still in the workshop
somewhere he cannot find. The reason is uncertain but possibly a combination of
excess moisture within the bamboo and the thinness of resin bridging the edge to
the centre. As Andy is accustomed to do whenever he starts turning a new piece,
particularly with an irregular
shape on the lathe, he was wearing his face shield, which did exactly the job as
its name implies.
(photos by Rick
Patrick & Andy Ogilvie)
<to
top>
May 2024
Spindle Revision
with
Paul Reeves
Thu 16th May at MWCC Club Night
To clarify, you use Spindle tools when all the
wood grain of your piece is running parallel to the lathe bed.
Spindle
tools include :
Roughing Gouges (rarely used
full name is SPINDLE Rouging Gouge);
Spindle Gouges;
Parting Tools;
Skew Chisels;
Form Tools;
Roughing Gouges are designed to be used
only for spindle turning and NOT on bowl turning. They are tough
enough to take the knocks required to turn a square into a cylinder so long as
you're careful with how much you bite in one go. Taking a large bite will blunt
the tool edge quickly; taking too much could bend or break off the gouge. This
is because they are of relatively thin, forged steel and often tang-mounted into
their handles and despite their name, cannot survive such rough usage!
They come in various sizes but all are best used with the bevel ground to 40º -
45º; a common mistake is to sharpen the bevel at steeper angles which will end
up chopping the corners off badly and tearing the wood.
Use with the handle down and move the tool along with arms and body together
while rocking sideways on your feet. The toolrest hand can deflect shavings away
from the face. Too much down pressure results in an uneven jerking cut;
moving too quickly normally produces a spiral finish.
Next to consider is with the gouge perpendicular to the piece, the surface
getting cut is arriving straight onto the gouge and getting levered upwards
which leads to a less than smooth tool finish. This is helpful for quick removal
but for the final pass, holding the gouge so that it is angled about 45º from
the perpendicular, the cutting edge is presented like a skew which will now
leave a shiny smooth finish. With a careful steady hand, you will produce a
straight surface. The only other shapes to make on a spindle are 'beads' and
'coves' with .....
Spindle Gouges. A bead is started by just
rotating and rolling the gouge anticlockwise along the toolrest for the left
side and similarly clockwise to form the right side of the bead. These movements
will only cut an arc equal to its bevel angle. To cut beyond that arc, the
handle has to be moved and lifted (because the diameter has become smaller) in the same direction and in coordination with
the rotation so that the gouge tip and bevel end up perpendicular at the desired
edge of the bead. This means the handle end has overtaken the tip.
For a cove, start with the gouge on its side, flute towards the intended cove
and use your fingers on the toolrest to balance & guide as you rotate the gouge
to end flute up at the bottom of the cove. As with the bead, the movement
requires coordination of slide across toolrest with rotation, handle descending
and when approaching the bottom, a conscious gentle push into the wood for the
bevel to stop the tip from digging in and producing a pronounced line where the
opposite cove side ended. Tools with long handles normally provide better tip
control - for every inch the handle moves the tip around the toolrest hand, the
short tool affects the tip movement far more than a long one. However, with
beads and coves requiring so much hand steering, a short tool makes it easier to
manipulate without your body getting in the way. Unfortunately, if the tool's
flute is short because of the metal has been ground back so many times, it may
be short but you are probably cutting with high speed steel rather than the
hardened which keeps its sharpness for longer use.
This gouge can also produce a straight surface by using your fingers as a
resistance or brake while your handle hand steers the tip so that it remains at
the same angle and distance over the toolrest with the cut running level. When
cutting towards the left, It is important for the flute to be angled towards
your left shoulder such that the cutting edge is just left & lower of tip centre;
likewise when cutting towards the right, use right shoulder and just right & lower
of tip centre.
Parting Tools are regularly used to accurately block out a smaller cylinder guided by callipers. They come in various shapes in an attempt to avoid friction when cutting wood which leads to swelling up and binding/grabbing on the sides of the tool.
A is diamond shaped rib to reduce friction; B is fish-tail, an old design with the disadvantage that although the blade reduces width from the tip, once you've ground back an inch or so to keep it sharp, the tool loses it wasp waist; Skew Chisels come to the rescue of a clean
finishing cut across the end grain of spindles. Parting tools tend to tear out
the end grain unless the wood is particularly close. With a Skew, you must only take off thin
bites at a time so that the removed wood is a thin disk being skimmed away.
Skews can also cut along the grain with a bit of care. Production turners
of yore and the Seiffen wooden Christmas Decoration turners of Germany today
used Skew Chisels for most (if not all) their
shaping. Skews come in many bar shapes and widths. As most of us have missed out
on the 3 year apprenticeship of Seiffen folk, the occasional user should select
a small width bar which has the advantage of producing a lower rotational force
in your hand than a wider bar would.
At all times, you are trying to avoid the
wood grabbing the cutting edge and twisting the tool out of your hands. This is
best achieved by raising the toolrest so that only the lower third of the tool
is in contact with the upper quadrant of the piece. In the photograph to the
right, you will see that when the trailing corner edge is being well
supported by the toolrest, the Skew is cutting away the wood with minimal
twisting force and neither corner is in danger of getting snagged. Keeping
wood contact within the green area makes the cut stable. Touching in the red area
is liable to twist the bottom edge of the tool off the rest and out of control.
Another useful cut with a Skew is a V-cut to transition the square top section
of a table leg (aka pommel) into the largest circle that the square timber can
form by enlarging the V shape until the groove is so deep that it nearly meets
at the centre of a flat side.
Form Tools - usually bead forming tools
are fine until they are used on soft woods. When they are wriggled from
side to side and the tool has cut down to near the crown of the bead, there is a
likelihood of the grain to chip out on opposing sides where it was very short and
parallel. The Spindle Gouge will make a better job with soft wood. The photos
below show how the Bead Tool is presented to the piece, i.e. groove downwards;
to help the wriggle action described above, note the outer wedge shape grind in
the 2nd photo and the last shows some home-made Form Tools, although the lower
is making use of the last bit of the flute so it is likely to be primarily mild
steel rather than the treated hardened steel that was there when first bought.
Another tool
(popular in USA) that can be used on spindles are Solid Tipped Carbide Lathe
Tools although they seem to tear most of our native timbers, but good with close
grain wood types.
Paul then produced a Policeman's Truncheon as an ideal project to perfect all the spindle shapes discussed above.
(photos by Rick
Patrick & Paul Reeves)
<to
top>
May 2024
DEMO 1
Gavel with
Paul Reeves
Thu 16th May at MWCC Club
Night
As there were several newcomers to the Club, Paul started off with some
Revision of Spindle Work.
An account of this subject can be found <HERE>
Honorary Member, Greta Reeves worked many years at Lymington Auctions and it
became practice that her boss would arrange for a replica of his own
Auctioneer's Hammer be turned as a retirement gift for long standing employees.
His original was of Cocobolo but the replicas were turned from more readily
available Laburnum. This original was tactile & small enough to grip the head
comfortably in his hand. Consequently, the handle didn't have to cope with
much blunt force and didn't need a strong thick connection to the head. The 3
examples below are Box, Laburnum and Mohonia.
The
head and the handle are both spindle components turned separately and
subsequently glued together.
Despite recent demonstrations venerating the 'Golden Ratio' of 1.618, the
dimensions of these gavels are such that the handle is twice the length of the
head. The length of the head was twice its own diameter. Additionally,
dividing the head into four gives a far better proportion for the two hammer
faces taking a quarter of the length each, leaving the neck between them for the
remaining half.
Head
A prepared cylinder of Laburnum was mounted between centres. Paul advised
against using sprung steb centres at either end as he found the sprung central
point applied to end grain tended to split the piece when under tension.
He had planned this project to have a 1½" face diameter, 3" head length and a 6"
handle.
He used a narrow Parting Tool to mark out the ends of the head and pencilled in
the quarters between them.
Using a wide Parting Tool making half-width overlaps, Paul quickly removed waste
from the neck.
Having prepared callipers to ¾" for the diameter of the neck, he used the
Parting Tool to finish blocking out accurately.
As both hammer faces were to be near spherical, he pencilled in marks around the
piece about ¾" from each end which is where the face would be at its maximum
diameter.
He then started making bead-like cuts off the ends gradually working back
towards the pencil line but leaving it visible. It was important to avoid
getting the end pointy; it should look more like a puffed-up cushion. The final
cuts were made while maintaining a slow, smooth and light-touch pass with good
bevel contact throughout. If your hands end up moving quicker than needed, the
bevel will lose contact/support and the tip will catch the wood and dig in.
The trick now was to turn the other end to match! If you have changed
hands when holding tools to work in the opposite direction from your early days
of turning, you will find that very helpful in this case.
The
next details were to put in a small cove centrally where the handle will go and
to finish off the hammer heads from the pencilled line back towards the neck.
Paul favours a small decorative feature in these beads called a quirk, which was
achieved with a 2mm ridge left about 20º down from the pencil lines so that a
Skew could create a shallow crisp-edged V-cut and the bead continues down to the
neck. This was only a tiny detail but it certainly helped to focus attention on
the heads.
One might think it more sensible to drill the hole for the handle earlier -
perhaps even while the Laburnum blank was a square. However, now that the
current dumbbell shaping is nearly finished, the patterns of the grain lend
themselves for you to decide where to drill the hole in order to show them off
to their best when the gavel is at rest on a desk. Once marked with an awl or
similar, one could finish the sanding and drill the hole once removed from the
lathe. For the demonstration, Paul drilled the hole on the lathe by eye using
smaller drill bits as pilots and gradually building up to the final size.
Using a Skew, he decreased the supporting end nibs to about 4mm diameter which would be strong enough to hold the piece while sanding. With the lathe speed reduced to alleviate the piece overheating while sanding, Paul prefers to follow the curves by supporting abrasives underneath the piece and taking care to avoid sanding away detail and decoration by sanding the shape and not sanding to shape. Laburnum will abrade down to 1200 grit or finer with considerable success but Paul was going to finish this piece with buffing so down to 400 grit was going to be sufficient.
Handle
Another prepared cylinder of Laburnum was mounted between centres. Once again,
Paul avoided using steb centres following a previous attempt turning a Mahonia
cylinder down to an 8mm tenon for inserting into the head, because it split as
soon as he tightened the tail stock.
He aimed to carry out all the shaping and decoration prior to weakening one end
as a result of the small tenon being turned. Paul also advised that if the
intended gavel was to be used while holding a longer handle rather than a grip
around the head, you might want to consider reinforcing the tenon with a steel
brad/nail.
He also planned to turn the piece with the tenon at the tail stock end so that
when checking fit into the head, it could be easily remounted in the lathe for
further turning.
The decoration was a homemade creation from an old square-ended scraper with 3
grooves made with the corner edge of a grinder wheel. This results in 3 evenly
spaced and shaped tiny beads. Because he had carefully spaced the grooves
relative to the width, he could easily increase those matched beads to 4 (or 40
of them if you wanted) by using a previously cut bead to fill an outer groove of
the tool and guide further matching cuts.
An elegant handle is all about shape and curves. Paul used a thin Parting
Tool to mark out the ends, the tenon and the diameter of a spherical shape at
the bottom end. He quickly turned away the bulk to leave a rough shape before
changing to a short Spindle Gouge to refine to the shape below. Be aware
that keeping the tips of narrow spindles cutting at the optimum height on an up
and down surface isn't easy and needs a gentle contact pressure throughout to
avoid digging in. With close grain woods like Laburnum, there will be minimal
compression of the spigot so that requires starting from slightly oversized and
gently approaching the necessary diameter with regular retracting of the
tailstock to check the fit into the head.
When satisfied with the cut shape, start sanding up to the edge of any
decoration but be careful not to wipe away small beads and sharp corners,
particularly with your initial grits; they can be polished up with the edge of
the finer grits when you progress to them. Whenever sanding spindles with
the lathe turning, keep the abrasive moving and keep in mind that it is sanding
across the grain fibres so they will inevitably stick up. A technique to
overcome this tendency is to stop the lathe and finish that grit along the grain
before changing to the next. Don't sand the spigot because if it fits, you won't
want it made smaller and besides, a very smooth finish doesn't help the glue to
adhere to the wood.
A Skew reduced the ends with a series of enlarged V-cuts to a very small
diameter (still stable because the wood is so dense) and finally parted off with
a fine toothed saw aimed away from the piece so that the tiny pimple left was
abraded away with the last grit used.
The head and the handle were buffed
with a light touch using a buffing compound so remember to put on personal
protection in order to avoid getting grit flying into your eyes. Remember to
buff off a surface, not into
it, or else the piece is liable to be ripped out of your hands. The final finish
was some micro-crystalline wax.
When sticking the handle and head together, thought was taken to line up their
grains sympathetically.
The June 2024 Competition was set to produce a Gavel
(photos by Rick Patrick & Paul
Reeves)
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I found it difficult to picture in my mind how to get 3 symmetric points out of
a solid with 8 vertices, 12 edges and 4 sided faces but then I remembered
something cubed is renown as a power of 3 and it does have 6 faces.
When Andy showed a finished 3-Point bowl alongside a perfect cube of wood,
one could clearly follow that the cube had somehow to be mounted symmetrically
between diagonally opposite vertices.
It was important that your starting cube of wood had 3 clean adjacent edges
because a small part of those edges furthest away from their common vertex would
comprise part of the finished piece.
It is possible to turn a thin walled bowl dependent upon the chosen wood.
Andy's example was of Brown Oak, which was close grained whereas an open grained
wood like Ash would prove difficult.
Andy had prepared a cube of Hornbeam with each edge of 100mm. This would
produce a finished piece whose points would be within a maximum 163mm diameter
circle. (Ratio of edge to span = 1 : 1.63 from Trigonometry)
Having decided upon the 3 clean adjacent edges, he proceeded to saw off the tip
of their common vertex in order for his tailstock to maintain a firm hold.
The opposite vertex was jammed into the headstock spindle with the aid of
non-slip matting. He took care to ensure the headstock end was in its correct
position by checking, using his toolrest, that his chosen 3 vertices were passing it at
the same position.
Top Tip
: Once the lathe is turning, these angled edges will fade from
view so be careful to keep fingers on your side of the tool rest.
Also, with it turning, you won't be able to see exactly when the gouge will
start to cut so ensure that first contact is always with the gouge's bevel as
you slowly move towards the piece with the handle held low. Upon contact, the
bevel will make a 'bumping' noise which will suddenly dissipate when you
gradually raise the handle and the gouge tip starts to cut.
Andy started turning away the 3 vertices nearest the headstock by taking thin cuts with each pass in order to avoid rip outs
as each edge reached the cutting tip. A high lathe speed always help with
irregular surfaces but it is important to avoid any 'greedy' deep cuts.
The spigot was to fit his 40mm set of C-jaws with a 7mm depth. Andy used his
thin parting tool to create the groove for the jaw lip at the bottom of the
spigot and then a similar groove half way up; this was for a later process.
Andy initially sanded with the lathe turning while using a power sander rather
than hand held abrasives in order to avoid the remaining sharp corners causing
injuries. He then stopped the lathe and hand sanded along the grain before
finishing with a coat of sander sealer.
The piece was then fitted into his C-jaws ready to hollow out the bowl. Andy
sawed off the newly exposed tip to accommodate support from his tailstock.
Taking care to avoid flying corners, he gradually turned away towards the centre
but leaving a stub for his tailstock.
As he cut closer to the flying corners, he regularly stopped the lathe to check
that his inside cut was keeping parallel over the entire length of the outer
edge of the piece. Any disparity quickly showed just how far down the cut
his Bowl Gouge needed to remove more wood to return the edges to parallel.
Halfway through the hollowing, Andy turned his toolrest into the hollow to avoid
a long over-hang of the gouge near the bowl's bottom.
Once satisfied with the inside parallel shaping, he removed the tailstock as
well as the stub to about 5mm from the bottom. Using a smaller Bowl Gouge,
he continued cutting to clean up the bowl's centre with just the chuck jaws
supporting.
When it came to sanding, Andy took care to avoid the abrasives
damaging any of the sharp edges. He didn't do any hand sanding with the
lathe turning, instead used his selection of various hard-backed shaped pads
without applying too much pressure. He found that his power sander with a
soft padding was ideal for sanding the central bottom of the bowl when applied
to the opposite side of where he was standing. With the lathe stopped, he
hand sanded to finish but again being careful of downward pressure near the
edges.
The piece was sander sealed and when dried, microcrystalline wax was applied
using some webrax.
The piece was repositioned so that the C-jaws now engaged the mid groove (formed
when turning the spigot initially) which made the parting off an easier process.
(photos by Rick Patrick, Andy Ogilvie &
Allan Rae)
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January 2024
DEMO 5
Racing
Cars with
Andy Ogilvie
Thu 18th Jan at MWCC Club Night
Design Plan
Andy described his own design as an example of what the woodturner needs to
consider.
The basic form of the bodywork is obviously a cylinder with a slightly reduced
round flat at the back end but with more reduced shape at the front end.
Andy wanted a flattish bottom to enhance the shape and reduce wheel diameter
required to clear the underside. He, therefore decided to glue two wood
blocks with the idea of offset turning to leave ⅔ upper body height of Sycamore
and ⅓ lower body of close grain window wood. The contrasting
coloured woods would help with the end decoration while the offset would lead to
the bottom block being left flat.
The next option to consider was whether to incorporate 4 individual axle-wheel
assemblies or 2 individual axles drilled through the body with a wheel at either
end or some other method. Clearly, it is down to you to decide which design will
create the least friction. Then whether the wheels were to be all the same
or different sizes from front to back, which in the latter case, would require
careful planning of where the axles were to join into the body.
Although the 'race circuit' hall floor will be perfectly flat so ground
clearance of a long wheel-base shouldn't be a factor, but a long thin car body
might
not be helpful when propelling by thumb and neither attractive nor a
realistic car shape. However, cars like an Austin Mini were very stable
with a wheel close to each corner. Andy planned a finished length of about 150mm with 2
axles about one fifth the length in from either end.
Body Construction
Andy had prepared the glued segmented rectangular blanks and had drilled two 8mm holes
about 30mm from the planned finished ends (i.e. allowing surplus to accommodate
the mounting centres) for 2 axles to go through the body at identical heights so all 4 wheels
are to the same diameter. He drilled a further 20mm hole about a
third of the way down the top from the back end for the cockpit. Doing this while the blank was
still rectangular made the job of getting all these holes exactly at right angles
to the body a lot easier.
He also drew on the intended back end, an arc to delineate the uppermost extent
of the bodywork.
He had found the central point of each end and made marks about 10mm towards the
bottom block at both ends.
To reduce the chance of the drive centres splitting the block apart at their
joint, he used a Pro Drive Centre in the head stock and a Ring Point Live Centre
for the tail stock to mount the blank between these offset centres.
Top Tip
: As Andy was right-handed and the front end of the car would
be 'downhill' from the larger back end, it made sense to mount the car's front
end into the head stock centre so that as he moved his gouge from right to left,
he would be cutting down the lie of the wood fibres.
The block was now turned down to the pre-marked
arc on the back end using a Roughing Gouge or a Skew Chisel. For the
demonstration, Andy used a planing cut with a Skew. Whichever tool one
used, care has to be taken to avoid using too much downward pressure into the
wood or else the pre-drilled cockpit hole will allow the tool to cut deeper into
one side of the hole.
Once he had turned a cylinder with just the bottom having a flat surface, Andy
used a Parting Tool at the intended front and back of the car to create some
working space for his Spindle Gouge to the rounded wedge shape in the photo
below.
The front end was detailed and left flat as shown in
photo below
for a radiator decoration to be added later.
The back end was left flat for exhaust pipes (pimping/embellishing an otherwise
plain back) to be added after the body had been parted off.
But before that, Andy reduced the lathe speed and used some abrasives via a
backing pad to protect hole edges He removed the dust before sander
sealing
the body to prevent any colouring bleeding into the wood.
Once that had dried, he applied some decoration while still mounted between
centres so that he could use the tool rest as a guide for marking in some
'go-faster' coloured straight stripes between the axles and an outline for the
engine bay.
Once parted off, used more abrasives and sand sealed the ends, Andy finished off the body decoration by drawing a radiator on the front end, remembering to add a 'race number'.
Axles & Wheel Nuts
The car body width ended up as 40mm wide so Andy allowed for additional
20mm per wheel per axle which totted up to 80mm axle length required. The
car body had been drilled with an 8mm bit so with a blank of over 80mm long
mounted between small centres, Andy prepared to turn an 8mm dowel but with the
headstock
end about 15mm diameter.
To maintain a length of wood to be a constant diameter does need a bit of
preparation. A common way is to use a Parting Tool and callipers set to
the required diameter and carefully reduce the oversized cylinder every 30mm or
so down to the required diameter and then join up the indents by cutting away
with a Spindle Gouge. However, Andy elected to demonstrate a method using
a spanner instead of the callipers by using an 8mm open-ended wrench.
Indeed, some people have shaped and sharpened their spanner's jaw tips to do the
cutting at the same time as the sizing.
Top Tip
: As most spanner jaws are deliberately manufactured very
slightly oversized for the sake of easy fitting, this feature helps one to avoid
turning away too much and the correct final size is achieved with a block and
abrasive. But bear in mind that most drill bits for similar reasons are
very slightly undersized.
After parting off the axle leaving a
small width of 15mm diameter to retain a wheel on its axle, matching Wheel Nuts
to match the other end were turned from the remnant blank transferred to a pin
or else o'Donnell chuck. The 15mm blank was first drilled out with an 8mm
bit held in Jacob's Lathe Drill Chuck before finally parted off.
Wheels
Having planned for all four wheels to be of 40mm diameter, Andy started with a
suitable rectangular blank (which he had pre-drilled at home using an 8.5mm bit
to ensure a loose fit on his 8mm axles for the sake of reducing friction), held
between chuck jaws and a point centre tailstock. This was accurately
turned down to a 40mm cylinder before carefully marking out identical widths to
allow a production line of wheels. Each wheel first had its outer face
cleanly cut with a Skew to shape the tyre and hub, a Point Tool to create the
join between tyre & wheel followed by burning by wire or Formica to create a
tread effect, then a small Spindle Gouge to create a curve of the inside face
down to a 15mm diameter to ensure the tyre avoids fouling the bodywork and
finally parted off to repeat the process another three times.
Exhausts & Driver
Andy drilled two 6mm holes in the back of the car body and with a suitable blank
between jaws and point centre tailstock, he used a Parting Tool to create a 6mm
dowel, a flared shape for the silencer and in again for the tailpipe.
For the Driver, the Exhaust blank was now turned
to the diameter of the previously drilled cockpit hole and a head shaped in the
first 10mm, narrowing to a neck for the next 5mm and then back out towards the
body diameter. After measuring the depth of the cockpit hole, parting off was
done so that the driver's shoulders would just appeared above the coping.
Andy then used a drum sander to create a dip on the top of the
body behind the line of the front axle and in front of the cockpit (see photo
below); this dip
would be where one's thumb could launch the car forwards.
All parts were cleaned up with fine abrasives paying particular attention everywhere there was a possible source of friction. Every part had its fitting checked before being sander sealed and allowed to dry thoroughly.
Assembly
It was now a case of finishing the colouring and
decoration before superglueing the various parts together.
Wheels were threaded (once correctly orientated) onto its axle before the latter was
glued to the body with just enough room for the wheel to turn freely.
The opposite end of the axle had its wheel correctly orientated and the Wheel
Nut similarly glued for that wheel to turn freely.
The axles were then trimmed and ends sanded.
Exhausts & Driver were the last to be glued in.
The February 2024 Competition was set to produce a decorated Racing Car entirely crafted in WOOD by you, shaped like a car and able to race in a straight line with a flick of one's thumb/fingers.
(photos by Rick Patrick, Andy Ogilvie & Ian Wright))
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December 2023
Light
Bulbs in wood with
Paul Reeves
Thu 21st Dec at MWCC Club Night
Paul started with a philosophical thought about
tonight's demonstration. Wooden objects can have a surprisingly long life. In
fact a Roman peppermill had been found at Hadrian's Wall and was still in
reasonable condition; there were also elaborate wooden artefacts in several
Pharaoh's tombs. It's a sobering thought that one of our own creations could be
around in hundreds of years time so perhaps we ought not to ignore that little
pimple or dimple in the bottom, else in years to come someone will be wondering
why we didn't take that extra time to get it right.
His Christmas demonstration was something a little different. He started by
commenting that Tungsten light bulbs last about 2000 hours, LED lamps 20,000
hours but his light bulb tonight could last as long as a Pharaoh's artefact.
He had chosen a piece of Hornbeam (which usually takes a good thread) mounted
between o'Donnell jaws and supported by a tailstock before using a Roughing
Gouge to turn a cylinder. In order to create a clean smooth surface, a Skew
Chisel with the point down was pushed across the end just short of the tail
stock.
Top Tip
: If making a string of bulbs, be sure to note the measurements
for replicating. The bulb dimensions look realistic if their length is about 1¼
to 1½ times the width and a 10 tpi chaser or similar is used.
A Parting Tool was used to reduce the end 2cm of the cylinder for the lamp
thread.
One could easily represent the thread with miniature beads but why not use
chased threads to give an authentic appearance. For a working screw thread, one
would normally leave a space at the left-hand end of the spiral so that the
chaser could be withdrawn from the cut in a continuous movement without
risking the threads tops snagging as the chaser hits the stops! This
thread is never going to be used so worn tops are of no concern.
The lathe was slowed to about 300-350 RPM and the
chaser was 'landed' on the piece with the leftmost 2 or 3 cutting edges touching
while Paul was smoothly moving the chaser from right to left but quickly
retracting before it buffeted against the larger diameter. He finished
with abrasives gently over and in between the threads to clean away any fibres.
Once completed, Paul moved the tail stock away and ensured the end centre point
was distinct before upping the speed and using a small Spindle Gouge to shape
the 'lead blob' at the very end of the thread while leaving the indent available
so that a hole could be drilled to allow for an eyelet screw to be subsequently
twisted in.
Returning to his ⅜" Spindle Gouge, he first turned a curve down to the thread
and then his 'long curve' technique was to very gently swing the tool handle
towards his body while keeping the cut tracking along the centre line aiming to leave enough
wood to support the piece (say 5-7mm) almost at the desired length. Paul
warned that while the shape might look fine horizontally on the lathe, it's
sometimes worth unscrewing the chuck off the head stock and stand the piece
upright to check how it looks in the direction it's going to be hanging.
Abrasives down to 400 grit were applied because the 'glass' surface has to be as
smooth as possible for colour to cover evenly right down to the line where it
fits into the 'metal thread cap' (created with his Skew). If it's not flat
enough, the colour will sink deeper in the grooves and won't end up an even
shade. Paul used some Lidl paint pens he had spotted last year but any
Sharpie/stain/ink/glossy paint will suffice. The threads were brushed
with gold gilt cream which gave a convincing brass effect. The 'lead' blob was
coated with silver paint. He used a hair dryer to shorten the drying period.
Paul used a small Skew to part off by slowly increasing the V-shape while
rounding off the top of the bulb.
That just left a run through the grits to smooth out the pointed round end and a
retouch with the paint pen.
(click above for close up view)
The examples in the above photo show that the RH green bulb is probably too long
for its width.
It doesn't have to be a plain colour. Paul had inherited some glitter paint from
a past Member which he applied to a second bulb. This was not only the
first time he had demonstrated glittery decorations but also the first time he
had ever used it, so we all learnt together that it needed to be thoroughly
shaken before use and that it was best to brush on fairly thickly as the
supporting clear varnish did a good job of smoothing the finish. Paul did
wonder if a coloured base coat might be beneficial the next time he made one.
(photos by Andy Ogilvie)
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October 2023
Toothpick
Holder with
Paul Reeves
Thu 19th Oct at MWCC Club Night
The majority of turned items tend to be from a single piece.
However, a Toothpick Holder requires turning several individual components which all have
to fit within each other, i.e. the knob, lid, caddy and body, which makes
for an interesting and rewarding project and arguably one that becomes more
relevant as we and our teeth age! One doesn't even have to worry about
food safe finishes.
The design of the holder is such that the lid rests loosely on a lip and
attached via a dowel to the caddy, which must be able to slide smoothly up and
down within the body.
To drill holes in wood (particularly deep holes) it is preferable to use a drill
rather than a box cutter to achieve the straight parallel sides required.
Even though hole cutting should be done at a slow lathe speed, it will inevitably
warm up the wood, so it is preferable to drill before turning away the outside
of the component because a thicker wall will be able to dissipate heat better
and less likely to split than might a thinner one.
Consequently, Paul prefers to start with the innermost cut and then turn away
its outside to fit the next holed component.
With that said, there are many turners who favour working from outside to
inside. The choice is yours.
From experience of previous holders he has turned, Paul had planned a
cylindrical blank for the body capable to accommodate his 32mm Forstner bit but
still leave sufficient side thickness to fashion some shape to the outside.
Most 'YouTube' examples show the knob and lid created separately, whereas
Paul prefers to turn these from a single blank. This method might well
create more wastage but if the body, lid and knob have a marked grain/spalting,
the end result will be much improved with all 3 parts matching and aligned.
Paul's lid had to be a diameter of a few mm greater than the 32mm hole so
it wouldn't fall in and able to accommodate at least 20mm depth for lid & knob
combined.
The caddy (ideally a piece of dry stable close-grained wood) needed to be
cylindrical blank wider than the 32mm so it could be turned down to fit, and be
able to accommodate his 25mm Forstner bit. The inside depth of the caddy should be about 25mm; if it was a bit more,
by the time one had added a 5mm base, the caddy tended to look out of proportion.
The diameter of his dowel proved to be too big for his 4.5mm drill bit but too
loose for a 5mm hole. However, he chose to go for the smaller drill
because despite tailstock and headstock supposedly being in line, inevitably the
drill bit held in a Jacob's chuck and the wood held in the headstock chuck will
introduce minute disparities that will result in the 4.5mm drill creating a
marginally larger hole because it was ever so slightly off-centre.
Top Tip
: When using a Jacobs Chuck, the
operation works well while under the positive pressure of winding the drill into
the piece, but upon withdrawing, the bit can bind onto the inside of the cut hole
and get pulled out of the morse taper.
Suddenly, a perfectly still drill chuck
with gear teeth has started revolving at the speed of the lathe.
Anticipate this
by supporting the chuck to stay in the tailstock with your free hand gripping it
clear of the gear teeth.
The Lid
Paul had chosen a piece of Laburnum (for it's stability, strength and finish)
and mounted it in his chuck. With his Jacobs Chuck in the tailstock, he
drilled a hole about 5mm deep for where the dowel would eventually be glued.
This end was to be the underside of the lid. With the Jacobs being replaced with
a revolving centre, the piece was well supported for turning to a cylinder and
squaring off the end carefully with a skew so as to not press the skew's edge
hard against the tail centre. The end 5mm or so was turned accurately with the aid of
callipers and a parting tool to 36mm then slightly tapered towards the tail
stock so as to help the finished lid to drop into position when it's let go. Then allowing
this worked 5mm to remain at
the tail stock end, he turned away the rest to fashion a knob - he chose a
dovetail shape. An advantage of using a wood like Laburnum was that it is so
close grained and strong that a small parting tool can produce smooth accurate
shaping. Before parting off, the piece was sanded.
The Caddy
Paul had selected a piece of 'Pride of India' aka Golden Rain Tree (Botanical
Name: Koelreuteria Paniculata) confusingly from China. He hadn't used it
before but it was purported to behave like Boxwood so should be ideal for this
job.
Having been mounted in his chuck, the procedure was similar to above other than
he used his 25mm Forstner first to cut about 25mm deep and then changed to his
dowel sized drill to drill a further 10mm. He removed the Jacobs; accurately
measured the internal depth for determining where the base would be and replaced
with a revolving centre to steady the piece for turning the 'fit-critical'
outside. (Should one/both ends of the caddy be a sloppy
fit inside the length of the body, there is a likelihood that the caddy will
tilt away from level as it moves up/down and jam its leading and diagonally
opposite edges against the inside).
With the piece supported between chuck and tail centre, Paul carefully and
gradually turned the outer surface down to 31mm diameter with the aid of
callipers and small parting tool, which worked perfectly provided the tool is
kept in motion back or forth.
(Whenever working with a wood type for your first time,
it is important to check regularly that the tool you're using is working as you
want, especially when using abrasives; eg sanding Yew too vigorously leads to
overheating and cracks in the finished surface whereas light sanding with rests
in between grits works fine).
The tail centre was removed so Paul could chamfer the inside edge of the
opening. To compensate for the missing tail support, he rested a couple of
fingers of his tool rest hand on top of the turning piece. As the piece
turns down onto the cutting edge of the tool, its natural reaction is to climb
upwards but the steadying weight applied by his fingers dampens the vibrations,
which would otherwise cause an uneven finish.
Light abrasives were used to flatten the surface before parting off at the
pre-measured depth plus say 5mm for thickness of base. This time, because of the
central hole drilled for the dowel, Paul could part off exactly on the
calculated line without worrying that the final cut would pull out some end
grain. The bottom was finished with sanding by hand.
Assembly
Bearing in mind that most commercial toothpicks/cocktail sticks can vary from 50-85mm; that the lid
is of about 5mm thickness; the caddy base is another 5mm and one will need some
space to pick, lift up and clear the caddy to remove (say another 5mm); it
follows that the hole depth in the body should be a minimum of 15mm plus the
length of your stick. Paul had sticks of 80mm so used 95mm as his minimum figure.
Paul glued one end of the dowel into the lid and allowed it to dry before the dowel
was sawn off 95mm below the underside of the lid and glued into the pre-drilled
hole in the base of the caddy.
The Body
A 40mm cylinder of spalted Silver Birch had been prepared with its end trued off
for mounting into the Club's chuck and a Jacobs chuck with his 32mm Forstner
drill bit in the tail stock. Paul stuck some insulation tape around the stem of
the drill bit at 95mm from the bottom of the cutting edge (which is
flat with a Forstner but often cone shaped with other wood drills which will
thus need additional depth to compensate).
Remembering the TopTip above, Paul reduced the lathe speed and keeping his
fingers gripping behind the gear teeth, drilled until the tape marked depth
reached the entrance hole. While drilling this amount of depth, he found he needed to withdraw the
bit to clear the shavings 3 or 4 times during the procedure.
He then swapped the Jacobs with a large diameter tailstock revolving centre to
steady the piece for shaping the outside.
Paul opted to create a gentle upward slope to where the lid would sit.
With the tail centre temporarily removed, he gradually turned a chamfered edge
within a few mm of the opening that matched the chamfer of the lid. With regular
checks to see how the lid rested in position, he decided upon leaving the lid
slightly above the body's edge. If the dowel had been left too long, one
could still shorten it before gluing it to the bottom of the caddy.
He chose to shape the sides with 2 coves using a smaller one at the top for
aesthetic proportion.
Spalted wood has areas of different colours which have different
densities that will wear down at different rates resulting in an uneven
surface. Treating the surface with sander sealer will help to reduce the
softer areas abrading away quicker than the denser areas.
With soft/spalted woods, 400 grit is about as far as you should dare whereas
with hardwoods, one could continue down to much finer grits.
Having re-checked the actual internal depth of the body and adding at least 5mm,
Paul marked the intended base of the body and proceeded to part off clear of the
mark because a parting tool will inevitably tear out when cutting end-grain.
He finished with quickly turning a jamb chuck so that he could reverse the
piece, finish off the base with a Skew and/or abrasives and even contemplate
some decoration.
(photos by Rick
Patrick & Paul Reeves)
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September 2023 -
DEMO 4
Decorative
Mushrooms
with
Paul Reeves
Thu 21st Sep at MWCC Club Night
Turning a mushroom is a perfect use for branch wood. Few projects can
so readily integrate bark, sap, heart and pith in a single piece. It
doesn't even matter if the piece cracks, splits, withers or weathers with age,
it will still look realistic.
Ideally, choose a wood with contrasting colours within its grain - although last
month's
Splash of Colour demonstration
could be incorporated when using a bland coloured wood to produced those
red-topped white-dotted examples.
A popular choice is Yew but Paul had brought a selection of more exotic branch
wood including Giant Redwood (Sequoia), Judas Tree, Juniper and Japanese Maple
as the example of a bland wood.
(All pictures
with a blue border can be clicked for a closer view)
1. Shapes
Mushrooms have quite a selection as illustrated to the right.
Turning is ideal with wet wood but note that most of the taller caps have deep
undercutting underneath, which is helpful in avoiding cracks/splits to appear
over time while drying.
2. Presentation
Solitary
pieces are the norm but to make an impression, try turning a group displayed on
a natural looking base, eg rotted or burred wood or a base covered in moss.
Mushrooms never stand precisely straight in real life so if turning a solitary
example, it looks better if you saw/sand a bit off the base to produce an
off-perpendicular piece. With a group displayed on a base, the pieces were
all turned with a 8mm spigot so that an 8mm drill could be drilled
anywhere on your show base and at any jaunty angle of your choosing.
3. Tools
A Spindle Gouge could do everything but it is easier for smaller sized tools
like thin/curved scrapers and hollowing tools for
undercutting the deeper caps.
Giant Redwood - Paul had mounted a piece of Redwood
between centres with the chosen end to be the cap placed against the drive
centre.
A Roughing Gouge was used to turn a cylinder from the tail end to about halfway.
Using a Skew Chisel, he turned a V-cut such that the left hand side remained
clear of the drive centre's edges and the right hand side starting to form the
shape of the chosen cap top while leaving a small stub for the drive centre to
continue spinning the piece.
Then with a Spindle Gouge, he continued shaping
the stem/stalk. If the piece is to be free standing, leave the base more
bulbous in order to lower the centre of gravity and improve stability.
Paul preferred to have his stem running thinner towards the cap and (depending
upon the wood) arranged to leave a bunched-up curved shaving just below the
underside of the cap to mimic the ring/skirt often found on a mushroom. This
annular skirt is the remnants of a sack-like veil originally connected to the
edge/margin of the cap prior to the mushroom starting to grow out of the ground.
He then repositioned his tool rest at right angles to the stem in order to
better support his gouge as he turned away the underside of the cap to
approximately parallel of the intended topside. He took care to avoid
damaging the bark remaining on the edge of the cap.
Continuing with his Spindle Gouge, he
continued with the cap's top surface without cutting it completely off.
He sanded all round with 180 grit only, commenting that real mushrooms tend to
have matt finishes.
Returning to his Skew Chisel, which works perfectly for cutting across the
grain, he turned off as much as he dared (about 5mm spigot).
Now it was decision time for parting off the base.
For standing alone pieces - saw off the base at an angle remembering to back off
the tailstock to reduce the squeezing pressure on the piece;
For mounting pieces on a base - while still between centres, create an 8mm spigot
before parting off.
Finally, the top was sawn off and sanded smooth.
4. Decorative
Options
PYROGRAPHY - The underside of the cap often has gills which can be
replicated by scorching with a carving blade iron. Once brought up to
temperature, drag the nib outwards towards close to the edge. Slower movements
produce darker & wider marks - if too dark, try brushing off with a toothbrush.
An alternative is a Dremel fitted with a disc cutter and then scorch with a blow
torch.
ACRYLIC PAINTS - Ideal for decorating plain woods with a brush or cloth. Drying time can be shortened with a hairdryer. Acrylic paste is a good way of creating a protruding white spot/scale over a red background.
WOOD STAINS - Another option to suit plain woods. See Splash of Colour demonstration for technique.
Button Mushrooms -
Although smaller overall, these mushrooms have comparatively thicker stems but
will still need a smaller drive centre than used above. Procedure much as
before other than Roughing Gouge removes all the bark and the smaller size led
to Paul turning 2 mushrooms from a single piece with a cap turned at either end.
Additionally, he used 240 grit all round to produce a shinier finish like the
real Button Mushrooms and he used a thin Parting Tool close to the stem for his
undercut.
These are prime candidates for plain coloured wood and wood stains.
Lobed Mushrooms - Paul had a piece of Juniper between centres, not necessarily on the pith but rather a point chosen equidistant from the various inward folds. One might think to be wary of the piece being out of balance but with such a size as small as tonight's pieces, there won't be any danger of the lathe walking itself across the workshop. Paul recommended that we treat it as a normal piece; in fact, high speed is your friend with odd shapes because the gaps pass quicker and your gouge is into cutting again with minimal deflection.
The finished Demonstration pieces
5. Other Ideas
A popular request from family & friends is a Tooth Fairy's Mushroom,
which has the stem fashioned as a box to hold the tooth overnight but magically
changes to a coin by morning time. It is recommended that the box is not
made big enough to hold a £2 coin inside!
Below is an example from Pinterest of a downlighter mushroom; the
reflection reveals a strip of LED lights embedded into the underside of the cap
that are powered by batteries secreted within the stem.
The October Competition was set to produce turned mushroom(s) incorporating a decorative feature.
(photos by Andy Ogilvie, Rick
Patrick & Paul Reeves)
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August 2023 -
DEMO
3
A
Splash of Colour
with
Paul Reeves
Thu 17th August at MWCC Club Night
Paul started the evening asking how many of those present had used colour in their
wood turning - (about 10%).
Then he asked how many liked to see colouring in wood
turned pieces - (again, about 10%)
This response validates Les Thorne's comments to the Club earlier this year that
he had stopped demonstrating various colour techniques due to a general lack of
interest.
Paul admitted he wasn't a fan of colouring for the sake of it but did believe
there were 3 occasions when colouring could enhance the finished piece :-
1. Spot Colouring
2. Liming Wax/Gilt Creams
3. Spirit Staining
Spot Colouring
Small
subtle areas of eye-catching colour(s) can emphasize an edge or boundaries of a
decoration on an otherwise bland blank.
As an example, Paul had prepared a pale Sycamore bowl which he proposed to lift
its plainness by adding some colour to the outer edge of the bowl's rim. To
create a surface to show off the paint, he had used the indexing facility on his
lathe to mark out 12 symmetrical points around the edge. Using a drum
sander with 120 grit mounted into his chuck, he just pressed the bowl edge into
the spinning sander to make a lozenge shaped indent. (Similar effects could
be achieved with the bowl mounted in the chuck and using a Dremel with a drum
sander or other attachments).
Although the centre marks had been precisely drawn, Paul believes to use even
pressure and movement by hand & eye to generate the indents so that the slight
variations in size and depth underscores one's hand-made craftsmanship.
As Sycamore is very pale, Paul had chosen bright contrasting colours of green
and orange.
There is no necessity to spend a lot of money on paints as there are many
discount shops (Lidl, InXcess, Milford Supplies) that sell an array of
acrylic paint pots.
TOP TIP
: To keep painted edges sharp and to help remove any
paint overspills, apply a sealer first as this will close up the timber pores
and provide a solid foundation for the paint. Any overspills can be wiped away
while wet or sanded away with 400 grit once dry.
He brushed on his paint keeping the paint thickness even and of alternating
colours. He carefully wiped away any paint that had settled in the wrong place
with a cloth before allowing it to dry completely - quickened with a combination
of lathe turning and a hairdryer.
He used fine abrasive along the grain to leave crisp edges of colour and finally
600 grit before tack ragging and a spray Cellulose sander sealer to seal in the
colour.
Paul had also experimented with staggered bevelling on both inside and outside edges of a bowl with an intention to paint the resulting upwardly facing wiggly line.
(click either above for close up view)
Liming Wax/Gilt Creams
These are designed to work their way into the grain of the wood to make them
stand out in a striking manner. They are particularly effective on deeply
grained ring-porous timber (eg Oak, Ash) where the pigmented wax can settle into
the grooves, accentuating the grain and adding a sense of depth and texture
often resulting in an enhanced rustic, antique feel.
Paul
had prepared a plain Ash bowl having a flattened rim with prominent grain.
After sanding and sealing, he applied a coloured acrylic paint as above.
Once dry, he used 400 grit to open up the wood pores again and used a soft brush
and tack rags to remove the dust.
White liming wax was applied into the grain covering the painted rim using a
gloved hand and then he wiped most of it off with a cloth before it was left
aside to dry thoroughly. The instructions on the wax jar talks about using
"finishing oil" but any mineral spirits (eg white spirits) should cure the wax.
Gilt Creams are predominantly available in gold, silver and copper, although
many manufacturers offer numerous shades of each metallic colour as well as
verdigris (green).
These bright/shiny flashes of colour are particularly effective in showing up
grain when the predominant background colour of the piece is very dark or black
from scorching/ebonising sprays.
Application is as with the liming waxes with the exceptions of being sparing
with the gilt (it's more expensive after all) and wiping off the cream with only
fresh unused sections of your rag/paper across the line of the pores to avoid
dragging all the gilt out.
If required, both wax & cream finishes can have added protection with clear gloss/satin lacquer spray.
(click either above for close up view)
Spirit Staining
Spirit
stains are remarkably good at bringing out the best in figured wood, but beware,
they are also good at highlighting any tool marks you have left on the surface.
When using abrasives, sand along the grain (which will be across the ripple).
The staining works best when a combination of colours are
selected to complement each other; typically a couple of dark colours applied
first followed by a light colour to produce highlights.
In the wine mat example to the right
A combination of staining and gilt creams is also very
effective.
In the bowl below, Paul had applied several coats of a permanent marker pen
within the decorative band and then sanded it back to reveal where the colour
had soaked into the pores. As the stain doesn't fill up the pores, his
application of Liberon Chantilly Gold gilt cream added a dazzling sparkle.
The September Competition was set to produce wood turned item(s) with a splash of
colour.
(photos by Rick Patrick & Paul Reeves)
June 2023 -
DEMO
2
Kitchen
Items
with
Paul Reeves
Thu 15th June at MWCC Club Night
There are many dozens of examples of utensils, apparatus, gadgets & aids
found in a kitchen.
Paul had brought 20 he had found at home along with examples of blanks he had
taken straight from his bandsaw. He also talked of teapot stands, trivets,
egg stands, mug rack stands, storage jars, cutting boards, biscuit cutters as
other examples.
(click either for close up view)
Wooden spoons are an obvious choice but rather off-putting when
you spend hours to produce something that costs less than £1 on the High Street.
However, most kitchenware from a shop is made from Beech so selecting a more
exotic or stunning grained wood can suddenly transform the mundane into
something extraordinary.
Just follow the spirit of the Bauhaus Movement's belief that functional items
don't have to look hideous.
Apart from the kitchen roll holder above, all the other
implements come into contact with foodstuffs.
Most bare woods have some degree of toxicity listed in wood databases. Beech &
Maple are rare exceptions so are most commonly used commercially, but many close
grained woods (e.g. fruit woods, box) would be acceptably safe. A useful habit
to acquire
for food preparers is dipping the wooden utensil in water before using.
It helps resist staining and pore absorption of raw food,
which could otherwise end up rotting beneath the surface.
Paul outlined the various ways of producing scoops, rolling
pins, roll holders & spoons. He warned of ever decreasing cardboard tube
diameters when designing kitchen roll holders and the dangers of turning spoons
out of a single blank. Still perfectly feasible, but needs awareness when
turning the bowl end, because the handle section becomes an invisible
propeller blade ready to thrash the unwary such that even a sadistic
headmaster would wince!
TOP TIP
: On some lathes (particularly if you have rotated the
headstock in order to increase turning clearance) the On/Off switch cannot be
reached as normal so plan how you're going to switch Off BEFORE you switch On.
Alternatively, the danger can be completely avoided by turning a handle (with a
spigot) & a spoon bowl from separate pieces and glue/thread them together afterwards.
Piping Nozzle
The Roughing Gouge was used to start creating a conical shape but leaving a 2 or 3mm square spigot at the outboard end. This spigot will eventually become a tiny bead that prevents the contents of the piping bag getting past the join between the nozzle and the bag when under pressure. At this stage, Paul just used his Parting Tool at 45º to cut off the two exposed square corners. The job would be finished to a circular bead with the finer abrasives at the end. (Diagram B)
The plan now is to hollow out the centre so that
there is a straight inside edge from a thin wall at the widest point to meet the
central drilled hole at the desired length of the nozzle. (Diagram
C)
Paul
used a Box Cutter to nibble away the inside of the drilled out opening to a
small depth and to a few mm from the outside edge of the cylinder. When using
this tool, it must be absolutely level.
Working with a Scraper, the handle is invariably higher than the tool rest but
if that happened with a Box Cutter, the hollowing would get wider than intended
as the cutting corner of the tool moved further away from the tool rest.
He checked the thickness and found the outside diameter (ignoring the bead) was
31mm while the inside was 26mm, making the wall thickness 2½mm. With this Maple,
Paul was happy to take it a bit more off. However, as the wall becomes thinner,
the tendency is for the piece to start vibrating and screech. This was countered
by a lighter bevel touch and supporting the piece with a couple of fingers on
top of the revolving piece.
Keeping
in mind the intended length of the nozzle, Paul continued passes with the Box
Cutter to achieve the required straight inside edge. He then worked on the
outside edge by increasing lathe speed and using his Roughing Gouge to remove
waste quickly. He finished with a recently sharpened Parting Tool slightly
tilted on the tool rest so that just the corner was being used. This works like
a Skew but is more controllable. Paul regularly stopped and used Outside Spring
Callipers to ensure the wall thickness was constant over the nozzle's length.
For the Piping to work efficiently. it's
important for the inside of the nozzle to be very smooth. When using abrasives
on thin pieces of wood, there is a tendency for the paper getting clogged and
heat friction quickly building up with a likelihood of the wood splitting.
Paul reminded us when using abrasives in our fingers, how quickly it gets too
hot to handle and then we reach for a sanding block! The heating effect
can be reduced by a combination of slower lathe speed and regularly clearing the
dust from both the abrasive and the wood so the abrasive is able to cut as
intended.
He also recommended new & unused abrasives because they would abrade evenly.
Paul made regular use of his small piece of carpet to unclog the abrasive very
effectively. He also changed the lathe direction between grits to cut off
wood fibres that had only been flattened by the previous grade of abrasive.
As the piece was quite deep, he used abrasive wrapped around a pencil to sand
the narrow part of the nozzle, which needed him to support the outside with his
fingers again as well as regularly clearing the dust. He avoided touching
the outside bead until he reached 240 grit.
For a really smooth finish, Paul recommended to dampen inside & outside surfaces
with water and let it dry before using the last abrasive grit. This will raise
any loose fibres and allow them to be cut away with the final sanding.
A Skew Chisel was used to part the nozzle off and
revealed that despite taking considerable care to check the wall thickness, it
still needed 1 or 2mm to be removed from the outside.
This was achieved by trimming a Jam Chuck with the corner of his Parting Tool so that the nozzle had a tight fit at
both ends.
With the nozzle jammed secure, the Parting Tool could then be used to trim the
outside surface as required. Serrations could be marked up for sawing should a
star-shaped piping be required.
All marking up was done with a soft graphite pencil to avoid leaving dented
marks and still be easily rubbed away.
The July Competition was set to produce wood turned item(s) you would find in a Kitchen.
(photos by Rick Patrick & Paul Reeves)
MAY 2023
Bowl from a Plank
with Paul
Reeves.
Thu 18th
May 2023 at MWCC Club Night
There wouldn't be a problem to overcome if the plank was 6" thick!
Obviously we are considering how to achieve a usable bowl with plank thickness less than
the height of the bowl.
Paul had identified 4 possible solutions using thin planks laminated one
above another.
♦ 1 : same sized solid circles in a tower - creates
the most wastage;
♦ 2 : increasingly stepped sized solid circles - still
a lot of wastage;
♦ 3 : stepped sized rings - using solid rings more
efficiently by dividing each into 2 or more rings;
♦ 4 : single solid circle with angled cuts - to create
rings so that the base of the next higher ring sits precisely above the top
surface of the ring below.
Option 4 is clearly the most efficient with the least amount of wastage but
the difficulty is to calculate the correct cutting angle to achieve it.
Consideration must be taken for the width of the tool creating the cuts.
Experience has shown that it is advisable to draw a scaled diagram to determine
the angle.
The Fishtail Parting Tool is similar in shape to the Basic but
has a slight thinning shaft behind the tip.
Paul's home-made tool was fashioned like a Bedan Parting Tool (i.e. end
cross-section as shown on the right) together with a more pronounced Fishtail shaped
cutting edge.
Planning Diagram
As the glued piece will have to be held in a chuck, the first job is to
decide which jaws. Paul had in mind a bowl size that could be held in C-jaws so
worked out where the spigot edge had to be. From that circle, he needed to
cut away a circular groove such that the C-jaws could clear the spigot and go
down to the bottom of the groove to ensure a good grip.
Paul's next decision was to consider a pleasing overall width of
the bowl and its ideal final thickness.
The smaller the angle of the cutting tool, the wider would be the bowl lip; a
large
angle would tend to produce a tall narrow bowl more like a vase.
If one wanted a bowl wall thickness of 12-15 mm, it would give the turner more flexibility
for shaping if the cut thickness was about 10mm wider.
Figure 2 illustrates that the desired bowl wall thickness
is produced by a larger dimension along the surface of the plank.
Additionally, the smaller the angle, the dimension along the plank's surface
needs to be even more.
Paul had drawn an accurately scaled plan of the plank in order to find the correct cutting angle - (xº in figure 3.)
Having found out that his Home-Made Parting Tool would create a
10mm cut, he planned the 10mm cut to run between A and B.
He wanted to go 3 layers high and start with a wall thickness of over 20mm which
would allow him to finish up (after shaping) with a wall thickness of about
10mm.
With these figures in mind, he decided to draw point D exactly 30mm from B.
The whole principle for the second layer to sit precisely on the bottom layer's
outer edge is for point D to end up at point C vertically above it. By
joining A to C, Paul could now measure angle x and found it to be 39º
The same principle occurs with D to E =10mm; E to G = 30mm; Point F can be found
and the angle of the cut is the same 39º
Mounting
Paul used a MDF disk connected to his chuck via a face plate ring. The
MDF provides a sacrificial depth that will help prevent the tool touching the chuck
and causing damage to both.
(click any above for close up view)
The piece of plank was secured to the MDF with double sided tape or hot glue.
If you use hot glue, run it out in a 'X' shape across the MDF to ensure all the
rings stay attached when being cut out.
Paul made use of the tail stock to aid getting the plank centred.
The spigot diameter was drawn on the plank and a Parting Tool was used to cut a
groove at right angles into the wood and enlarged to about 10mm wide plus a
small cut-in at the base so the C-jaw would be able to get in to grip the
spigot.
The next 3 cuts were the angled ones all the way through the plank with Paul's
Home-Made Tool. Paul commented that he would start from the outermost cut first
in order to help the inner piece of plank remain firmly stuck in position.
To help keep the tool cutting at the right angle, one could use a slab type tool
rest with the required angle marked on its top face. However, Paul used a
magnetic digital angle tool (from Lidl) which he fixed on the banjo and provided
a straight edge guide he could parallel.
(click any above for close up view)
With the plank cut into 2 rings and a circular base, the pieces were removed
from the MDF faceplate.
Paul had drawn a pencil line prior to turning which would be helpful to get
grain to line up once the 3 layers were turned over and laid on top of one
another before they were glued, making use of the faceplate supporting the top
layer and the tail stock keeping the bottom layer pressed hard against the
others while the glue dried.
(photos by Andy
Ogilvie, Rick Patrick & Vic Russell)
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Andy explained that following a visit to a workshop of fellow Member, David Game, he was fascinated by some twisted polygon shapes known as Streptohedrons (aka Wobble Balls in USA). David had discovered examples on a website by Englishman, David Springett (alas no longer alive).
'Strepto' is Ancient Greek for "twisted" while 'Hedron'
describes a "geometrical solid".
Streptohedrons are created by splitting a piece of wood and re-gluing them
together, turning a shape before splitting and then re-gluing again BUT
only after twisting one of the splits.
After band sawing the wood,
Andy had planed both sides to make sure they made a flat joint. The join is done with
glue (typically PVA) on each joint face sandwiching a piece of newspaper/paper, which will be
strong enough to hold the halves together on the lathe but still be able to
split again despite absorbing glue. Glossy paper should be avoided as it tends
to restrict the absorption of the glue.
Cup centres were used on the lathe in order to reduce the chance of drive and
tail centres prising the piece apart with only their central pins pressing
against the join.
To make a successful Streptohedron, you must plan to have a shape with rotational symmetry (i.e. when a surface can be rotated and it exactly matches its starting surface) so that when the halves are twisted to the desired symmetrical position, the joint faces will still fit following shaping with your turning tools although some sanding will probably be required.
StreptoHex
Andy had selected a 3" cube of Yellow Ash, which
he had prepared at home by band sawing it in half, gluing as above, mounting between centres (with the
joint running from head to tail stock) to turn a spigot for his chuck (which
helped to secure the glued halves together) and finally turned
to a cylinder so that the length exceeded the diameter sufficiently to allow
space for working tools at the drive centre end of the piece.
This was mounted on the Club's lathe. The cylinder was trued up; the end was squared off and the final diameter measured. His plan now was to turn the whole piece so that the join surface changed from its rectangular shape into a 'regular' hexagon, which required either a bit of technical drawing or some mathematics to work out the correct dimensions.
From the diagram above, he needed to work
out the lengths of AB and Cm.
Since Andy had just measured the diameter, he could calculate the radius (AC) and drew a
circle with compasses (either at true measurement or scaled) on a piece of
paper. Choosing a convenient point on the circle, he marked 6 arcs along the
circumference using the same compass with the circle's radius to map out the 6 corners
of the required purple hexagon above and measured the two required lengths.
Alternatively using formula & trigonometry, the
internal angle in degrees of a regular polygon with 'n' sides is 180(n-2)/n. A Hexagon's angle
is therefore 120°, which means angle 'a' = 60° and the triangle CAB must be
equilateral, so AB is the same as the radius AC. From trigonometry
Cm = AC x sin60°(which
is 0.866)
Andy's demonstration piece had a
diameter of 60mm,
which meant AB was 30mm and Cm was 26
The cylinder was marked up with a centreline 26
mm from the newly squared off end and another mark 26mm closer to the head stock, which would define the other end. Finally, a 30mm circle was marked on the cylinder's end.
Starting out with a Spindle Gouge and finishing with a Skew, Andy turned away the Ash piece to leave a smooth cone shape between the centreline and end surface circle marks. Using his parting tool, he started to part the piece at the head stock end to the same depth as the end face. For our demonstration piece, that depth was to leave a 30
mm circumference which he had set on his callipers. Andy then gouged out between this last cut and towards the head stock to give himself room to turn away a matching smooth cone shape towards the head stock.
(some photos in this
demo can be clicked for close up views)
Andy had a selection box of different shaped sanding blocks so he could sand all flat surfaces carefully without damaging any sharp edges/corners. He then sealed all surfaces with Sander Sealer before applying some Yorkshire/Hampshire Grit to smooth and polish using his applicator of choice - his old socks!
Femisphere
As with the previous demonstration, a blank block (this time of Mulberry) had
been prepared by being band sawed in half, re-glued, spigot turned with the
split running from head to tail stocks.
The prepared blank was now mounted on the Club's lathe & chuck where the
cylinder was trued up, the end squared off and the final diameter measured.
Instead of a hexagon, the Rotational Symmetry face this time would be a
distorted plus sign.
From the diagram above, you
can see that the blank was turned to a cylinder that ended up as 46mm
in diameter.
The plan was to turn away identical quadrants to leave 10mm
edges at each cardinal point. This meant that each quadrant would have an 18mm
radius. The cylinder was marked at 18mm, 28mm
and 46mm from the tailstock end plus a 10mm
circle drawn on the end face.
Andy admitted that he had deliberately arranged for the cylinder to be reduced
to 46mm because he already had a 36mm
button in stock, which would act as a perfect template in keeping the curves
identical on each end of the piece.
Working on the tailstock end first with a Spindle Gouge to get a curve close to
the first mark and the 10mm circle, he finessed the work
using a Round Nose Scraper with regular checks against his template button.
Before starting the headstock end, Andy parted down towards a 10mm stub at the
46mm mark and turned away waste to make space when using
his gouge/scraper. This needed gentle passes of the cutting tools because of the
weakened support from the reducing stub size as he progressively parted away. (There
are some Conical Tip accessories for live revolving centres which would improve
support.)
He subsequently needed to create more space in front of the stub to accommodate
checking with his rigid template.
Once the inner quadrant shape was finished, he parted off purposely leaving a
small nib and proceeded as in the previous demonstration with effect from the
TOP TIP : above and ended with the rather tactile shape shown below.
Bibliography:
David Springett : 'Woodturning Wizardry' & 'Adventures in Woodturning'
The
Bridges Archive - < link >
(photos by Andy
Ogilvie, Rick Patrick & Vic Russell)
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January 2023 -
DEMO 5
Buttons
with
Paul Reeves
Thu 19th Jan at MWCC Club Night
Why would anyone want to turn buttons?
They are readily available very cheaply from shops/internet although they
generally tend to be of poor quality. If you have turned them yourself,
one commonly thinks of them as something special.
For example, the Wife of one of our Members makes bespoke handbags/clutch bags,
which are elegantly finished with a stained or natural wooden button to
complement the design and avoids that 'mass-produced' look.
Coat Toggle
One of the simpler fasteners is a 'toggle' commonly used on Duffle coats.
Paul had a piece of composite ply made from compressed colourful Maple prepared
between centres, which he turned to a cylinder. He then marked out the two
ends and the centre appropriate for the intended button hole/loop. Over the
years, Paul had fabricated his own scraper-type tools from old chisels and even
from a 1" wide commercial hacksaw blade, although that had to be heated several times to reduce its brittleness.
Having selected one of his homemade scrapers, Paul skewed from centre towards
each end to shape before finishing out a cove around the centre to accommodate
the fixing twine using a gouge.
Drill Jig
It is difficult to drill sewing hole(s) accurately and get each button looking
identical. Any misplacement will appear obviously out of square. Even with
a single toggle hole, the starting hole is easy but difficult to get it to
emerge within the cove on the opposite side. It is well worth preparing a Drill
Jig to fit in your tool rest banjo and thick enough to provide a pilot hole
which will hold a drill bit to turn steadily without any wobble.
Paul took advantage of the lathe's ability to lock the chuck into a
fixed position and used a 5mm drill for this size of toggle.
With the shape & hole completed, abrasives were used through the grits, (finishing off
by being applied along the grain). Some wax / friction polish / lacquer
could be applied before parting off. In order to get a clean cut to the
toggle ends, Paul used a Skew Chisel with its point downwards.
(click this
photo for close up view)
Small Buttons
To make a production line of identical small buttons, it is best to turn a
cylinder of wood to the diameter required for the button hole and mount in
o'Donnell jaws. Paul had chosen to start the demonstration with end grained wood
which needed to be a hard wood like Box (as lesser
close grain woods will probably be too brittle). As small thin buttons
have little wood to waste, the turner needs to reduce the number of abrasive
passes, so keeping tools sharp and regularly diamond-filed will help.
Having squared off the exposed face, Paul turned a shallow dent
in the centre of it to allow room for stitching to be wound through the sewing
holes without adding thickness to the button. He then rounded all corners to
help the button pass through its button hole.
The sewing holes for this size button needed a 2mm hole in the Drill Jig. The
pilot hole was adjusted so that the drill
was lined up parallel to the lathe rails and at a height that
would start just inside the shallow dent. As there were 4 holes to drill,
Paul hand turned the chuck until the gap between adjacent jaws was vertical
before locking the chuck position. When ready to drill the next hole, turning
the chuck to get the next gap upright meant it had turned 90º
and so on. Paul advised not to be tempted to drill deeper than needed for
a single button because the further the drill bit is away from the pilot hole,
the more likely it will wander from the required position for the following
buttons.
Paul parted off with a narrow parting tool but said he was ready to support the
button face with a finger in order
to avoid 'chatter' marks. He also warned to go steady when parting through
the sewing holes to avoid 'pull out'. It would also help preserve the
stitching by chamfering the edges of the holes with a slightly larger drill bit.
Larger Buttons
Any button over about 2cm diameter lends itself to added interest, whether that
be from using interesting pattern/coloured cross grain wood; or using decorative
tools (eg Chatter Tool, Decorative Elf etc) to create patterns; or using
colours/waxes (eg ebonizing, Liming) to fill in or frame the buttons.
(click any above for close up view)
With slightly larger blanks,
sometimes you are able to mount them in the gaps between the o'Donell jaws while
still square.
As with the Small Button procedure above :- turn a cylinder; trim end up square;
dent with slope down towards button edge; pencil mark circle for where holes
will be drilled. Any texturing should first have its preliminary surface
taken to its final finished standard.
Next, apply your decoration, colour or wax before drilling holes and parting
off.
Top Tip
:
In order to avoid damaging the
detail created, take care when using abrasives / cutting paste/ buffing.
In the case of waxes, apply Acrylic Sealer before any other finishes.
Shank Buttons
These buttons have a fixing hole within a post on the back of
the button rather than on their faces.
The technique when using a Chatter Tool is to have a slower speed & move
the tool rest further away than for a gouge.
The shank was formed with a Parting Tool once the face was finished. Paul
created a 5mm shank to accommodate a 2mm fixing hole.
He used a Skew (with point down) to part off.
The January Competition was set to produce at least 2 examples of
buttons/fasteners turned out of any appropriate material.
(photos by Andy Ogilvie, Rick Patrick & Paul Reeves)
DECEMBER 2022
Wood Thread
Cutting with a
Screw Box
and
Tap
with Paul
Reeves.
Thu 15th
Dec 2022 at MWCC Club Night
(click any photos in this
demo for close up views)
You will need a matching set of Screw Box and Tap.
A size suitable for cracking nuts would be about ¾" diameter.
A close grain wood would seem a better choice but Paul has had mixed results
when tapping into hard wood end-grains as the resulting threads would often
crumble away.
He found that threads were more sturdy when cutting across grain for hard woods.
TOP TIP
: If using soft wood, tap
into the end grain after allowing some thin supaglue to soak into it. This will
stabilize the resulting action of the cutter as it produces a thread.
Making a Nutcracker
The Body
For the demonstration Paul had prepared
a 3" square by some 6 to 7" length of Hornbeam to mount into a chuck.
The width of the holding bowl will depend upon which nuts you are intending to
use : small nuts like almonds/hazel nuts would need about 1" diameter whereas
larger nuts like walnuts would need more room. (Probably best not build one for
a Coconut!)
In order to accommodate walnuts, Paul fixed an 1¼" diameter Forstner bit into a
Jacobs Chuck held in the tailstock marked for a depth of about 2" - this would
allow the walnut to be inside enough to be held steady rather than catapulting
out the opening when applying pressure with the screw crusher.
With the bowl hollowed, the Forstner was removed.
A hole in the side was drilled with a size slightly less than the Tap's
diameter. (If you study the photo above for the ¾" Screw Box, you will
notice Paul's Father had placed a ⅝" flat
hole cutting tool as a starting point but Paul chooses to use a slightly larger
Forstner)
The Tap is going to form the female thread. Once the Tap has started a thread,
it will need to be reversed a quarter of a turn after about every half turn in
order to clear the cutting debris.
With the thread completed, the outside was turned and shaped into a barrel with
the thread hole at the fattest dimension.
TOP TIP :
When your gouge passes over the thread hole, you will
need to avoid any excess weight into the wood or else you will end up with a
dent/cove in line with the hole.
Keep a check where the bottom of the hollowed bowl is relative to the outside in
order to avoid shaping the handle too close and weakening the piece.
Abrasives were used through the grits but again, being careful of around the
thread hole or else it would end up elongated. The first grit has to rid the
scratches left by the gouge, while the finer grits get rid of the previous
abrasive marks.
The piece was turned around and a Jam Chuck was used to drive via the Forstner
hole.
The original spigot was turned away to a thin support, but strong enough to
maintain the piece against the Jam Chuck. The thin support was sawn off and
abrasives applied to finish.
The Crusher
A square blank of Hornbeam about 8" long was mounted between centres and turned
to a cylinder at the required diameter for the chosen Screw Box size.
The length of thread required on the dowel was measured from the outer edge of
the bowl though the thread hole to the opposite inside edge. A further 1" was
added to compensate for the distance the dowel has to go into the Screw Box to
reach the thread cutter, which creates the male thread, and for the space of a
chamfer to be turned at the end point of the thread (to help avoid damaging the
thread as it contacts the nut or else the curved inner surface of the bowl).
This is best achieved accurately by use of a Skew Chisel held with the long
point down.
Unlike the Tap procedure, the Screw Box
technique requires turning the dowel in the same direction (without any quarter
turns in reverse) so that the off cut exits the box without breaking off and
jamming inside.
A handle was then turned and sanded before being sawn off at the chamfered
bottom of the thread and at the top of the handle.
TOP TIP :
If using softer woods, a hard tip could be added to the
bottom of the thread with a hob nail or gluing a button of hard wood, eg Box,
Rosewood etc.
(photos by Rick Patrick & Paul Reeves)
October 2022 -
DEMO
4
Animals
with
Paul Reeves
Thu 20th Oct at MWCC Club Night
The Internet can show a confusing scrapbook of
examples but googling, for example, "animals for wood turners" should be able to
give you more focused ideas.
The challenge to produce something unique is to see a picture of a finished item
and then use your experience and wits to work out how to achieve it rather than
just following instructions from start to finish.
Paul had seen a picture of a hedgehog and thought he could improve it with an
up-turned snout using 'Off Centred Turning' principles and some 'Texturing' to
suggest a prickly coat.
(You can find both of these techniques described in our previous demonstrations
<HERE>)
When approaching a project where you have to work out the way of doing things,
it is likely that you will need to experiment on your first attempt. Paul
confided that the finished article he had shown at the start was his second
attempt and that he had adapted it from his initial plan.
HEDGEHOG
He
didn't need a big piece of wood - he had selected a 100mm length of 40mm square
and marked diagonals on both ends. To achieve the eccentrical turning to come,
he marked the centre and a small offset up one diagonal with a larger offset on
the other side of the centre mark. He repeated this at the other end taking care
to mark the same offsets adjacent to the same side edge.
The large offset would be used for the animal's underneath and one of the small
offsets would be used to form the face.
The Body
With the blank mounted between centres, Paul turned it to a cylinder
and then marked out the desired length of the hedgehog while ensuring that each
end had sufficient remaining wood to be strong enough to support the head and
tail drives for subsequent texturing and offset turning. He rounded off the back
end of the animal (without parting off) and tapered the face end.
It was important to sand before texturing because it would be impossible to sand
anything afterwards without spoiling the texture effect.
Paul's texturing tool was a
metal-worker's Knurling Tool (although similar could be achieved with others
available eg Henry Taylor Decorating Elf). To obtain the best result, Paul
maintained a positive inward force to keep an even pressure on the cutting
wheel(s) while the tool was moved along the tool rest making contact parallel to
the surface of the piece.
Paul finished the body with some appropriately coloured stain applied with a
cloth.
The Underneath
With the blank now centred on both large offsets AND checking by hand-turning
before starting that the piece cleared the tool rest, Paul started turning away
the hedgehog's underneath. This called for smooth movements because of the the
intermittent contact of the cutting edge of the gouge. The back and front ends
were rounded away but importantly, NOT turned away more than the central axis of
the starting cylinder (which of course is not the same as the central axis of
this current configuration). Paul's intention was to get the end of the finished
nose at the original central axis.
The underneath was then sanded with abrasives on a hard flat block held rigidly
perpendicular to the turning surface such that it only sanded the newly turned
surface without affecting the edge of the textured surface.
The
Face
The piece was configured with the headstock driving the central spot and the
tailstock holding the small offset at the hedgehog's face end. Paul turned away
the cylindrical wooden block end carefully so as to preserve the original
cylinder's central spot, which allowed better access to turn away a curved face.
This was sanded with a flat block as above before reconfiguring both stocks to
the original centres.
The tail and snout ends were turned away to almost parted. A Skew was the
preferred gouge to finish off the cross-grain ends to thin stubs, which were
then sawn clear.
The new cuts were tidied up with abrasives and fresh coloured stain applied to
the tail end.
Paul set the headstock with a block holding an abrasive disc with Velcro in
order to put a flat on the underside to aid stability.
-----o00000o-----
ELEPHANT
Another turned animal that caught Paul's attention was an Elephant, but very
much in a Scandinavian style rather than life-like. The design was clearly in 4
separate pieces connected together; possibly by dowels or perhaps by gluing
flattened bearing surfaces.
Inspired by the thought of a pink Elephant, Paul chose his recently planked
Redwood. This is a soft and slightly brittle wood so a ring centred tailstock
would be best.
The Head & Trunk
He had prepared the body prior to demonstration as it was a simple shape. Paul
felt the stylized head and trunk shouldn't touch the ground nor be much higher
than the body. He shaped and sanded before removing from the centres with a Skew
Chisel across the end-grain.
The
Ears
With an appropriately sized square blank, Paul had band sawed it in half and had
taped the halves together again with double-sided sticky tape applied to the
ends. (This can be done after turning but it helps to keep the ends square). Both drive and tail stocks needed to be ring centred types to avoid the
piece from splitting apart while turned to a centre. Having ridden elephants
himself while holidaying in Asia, Paul could vouchsafe that their ears were
quite triangular so he turned the cylinder into an oval shape before sanding and
then removing from the blank using a Skew. This resulted, after separating, into
a rounded triangular shape.
For assembly, he carefully checked where the various components would need to be joined so he could then sand flat the corresponding surfaces using the circular Velcro-holding disc above ready to be hot glued together.
The November Competition was set for a
turned example of an animal as a stand alone piece
or
else on / in something relevant.
(photos by Andy Ogilvie, Rick Patrick & Paul Reeves)
Taking on the
Kilner Challenge with
Andy
Ogilvie
Thu 15th
Sept at MWCC Club Night
As an enthusiast of being given a challenge rather than following someone else's
'recipe' of turning procedures, Andy accepted the 'Kilner Challenge' :-
To create an air-tight container like the renown Kilner Jar.
Following the standard plan of "Research -Theory - Practice - Refine," it looked
like he might fall at the first fence!
No amount of Google searching revealed anybody, anywhere able to supply the wire
hinges used by Kilner.
Neither could he devise a curved, hinged alternative made of wood; so his only
alternative was to cannibalize the wire hinge contraptions from an old Kilner
jar.
The closest he could find was that Asda had medium jars and clip top spice jars
on offer for £1.20 (as of Sept 2022).
It turned out that this was helpful as it became clear that whatever size of hinge he used, it could not be adapted nor adjusted. Consequently, precise dimensions at the bottom of the lid and at the top of the jar were required for them to come together parallel and have any chance of the finished item being air-tight.
Before Andy started off turning wood, he prepared drawings showing all the
crucial distances & circumferences between the wires when closed, from accurate
measurements of his wire hinges 'stolen' from a 4" diameter jar.
These drawings were set and orientated correctly in his line of view from in
front of the lathe.
Andy had turned a lid and a base at home and found ways to refine the design which he would highlight at the end of the demonstration.
Turning a Lid
Andy had prepared a 4" square blank of Ash mounted in jaws and turned it down to a
95mm cylinder.
Working from his drawing and using an Outside Spring Caliper, Andy carefully
reduced the end 9mm to an 80mm diameter cylinder. (This could be achieved with
Parting Tool / Spindle Gouge / Skew - whichever preferred)
Using a thin Parting Tool and the Caliper, he turned a notch to a 76mm diameter,
which matched the internal diameter of the rubber seal (also cannibalized from
the Kilner Jar). This was subsequently turned back to the 95mm diameter as per
his drawing.
Similarly, a 3mm notch with a wider Parting Tool was turned to an 86mm diameter
at 11mm above the previous notch to accommodate the wire frame for the lid.
Next, the bottom of the lid was hollowed out while keeping in mind to keep the
resulting wall thickness strong enough to withstand any forces from the wire and
seal.
An appropriate groove was cut inside this hollowing to suit his chuck jaws in
expansion, which would be needed to reverse chuck the lid.
Finally, the top of the lid was rough shaped WITHOUT parting off.
The sides, notches & hollow were carefully sanded to crisp edges before reverse
chucking and finishing the lid top with gouge and abrasives.
The wire for the lid can be separated at the hinge and its loop be expanded over
the side of the lid before engaging the appropriate slot and re-engaged with the
hinge. Similarly, the rubber seal was fitted into its notch.
Turning a Base
Some thought should be given to which type of
finishing to use.
As the most common contents of these jars will be foodstuffs, a 'food safe' oil
or wax should be considered for at least the inside surfaces.
Refinements
Andy explained that his first wooden lid & base attempt for a single jar was
a design he subsequently rejected because it prevented the user to visually
identify the contents, whereas a glass jar is obviously not as limited.
However, adding wooden lids to glass bases or wooden bases to glass lids
overcomes this limitation and certainly enhances their style.
Another possible enhancement was by adding a
flower decoration, which Andy demonstrated after the tea break using Box with a
Purpleheart insert (shown above).
Finally, Andy produced a wooden top version for a Kilner bottle that he had made
at home to complete the Kilner range as well as his Challenge for the night.
<to top>
For clarity, games like Solitaire (although they
involve many turned parts) are not considered a puzzle in the sense we mean
tonight.
We are looking for a teaser that cannot be easily or readily solved.
For example, Paul's Ball & Beehive puzzle with its apparently disappearing ball,
is a precisely turned piece with a very thin walled half ball within a segment
of a model skep (ancient straw beehive).
Lipstick Puzzle
The Puzzle Maker demonstrates to his
punter that the inner lipstick is able to slip out of its tube by turning it
upside down.
The task is to remove the inner lipstick without tipping it over. The stick is
annoyingly smooth, pointed and barely above the rim of the outer box.
The skills required of the woodturner are to fashion the lipstick to a close fit
of a perfectly parallel inside wall of a box and at just the right height to be
unable to grip with fingertips. Also, as a contrast of colours appears more
striking, choose woods that have stood long enough to have stabilized their
moisture content and are of varieties unlikely to shrink/swell differently to
each other on dry/wet days.
The best way to achieve the parallel wall is by using a drill held within a
Jacobs Chuck in your tailstock, (although if you don't have these tools
available, next best is a Box Cutter).
As accuracy of this cut is paramount and there can be a tendency for a drill to
'walk' on its first touch, you might consider using a Centre Drill Bit (aka Slocombe Bit) which are designed to provide a starting hole for a larger-sized
drill bit.
¤ The Box Section
Paul mounted a rectangular block clenched between the side edges of his
o'Donnell jaws and turned the exposed end to a cylinder of sufficient length for
the outer box.
A Jacobs Chuck was fitted to the tailstock and Paul selected an appropriately
sized Forstner bit with a toothed rim. Originally, a Saw-tooth Bit was used for
drilling down end grain and a Forstner Bit for cross grain.
The lathe was set to a slow speed and a hole was drilled to about 30mm depth.
Top Tip
: When using a Jacobs Chuck, the
operation works well while under the positive pressure of winding the drill into
the piece but upon withdrawing, the bit can bind onto the inside of the cut hole
and get pulled out of the morse taper. Suddenly, a perfectly still drill chuck
with gear teeth has started revolving at the speed of the lathe. Anticipate this
by supporting the chuck to stay in the tailstock with your free hand gripping it
clear of the gear teeth.
Having checked the depth of the hole, Paul marked
where he planned the base of the box to be with a narrow Parting Tool and shaped the outside to a thinner
body. He sanded through the grits on the outside and also, more importantly, the
inside using abrasives wrapped around a pencil.
To add interest, Paul used his Decorating Elf, brushing off resulting fluff
with a stiff bristle brush, used a Point Tool to define outlines and then a Taut
Wire to burn mark them taking care to keep the burn colour similar.
He parted off (still using double width cuts to avoid
jaming up his Parting
Tool) and then converted what was left in the jaws into a Jam Chuck to fit in
the drilled hole for reverse turning in order to finish the base.
He removed any centre pimple with a sharp Spindle Gouge or a shallow pointed
Skew, which cuts end grain very cleanly.
Paul applied decoration to match the sides although the circular burn marks had
to be done with a formica edge.
Finally, a touch up all round with abrasives, gently done to avoid any shrinkage
through sanding heat.
¤ The Lipstick
For a contrasting colour and lighter weight, Paul mounted a Sycamore blank as
previous.
Paul quickly turned it to a cylinder larger than the drilled hole of the box so
he could then carefully turn away the end with a Parting Tool, little by little,
regularly checking against the hole until the end could slide in & out without
any slackness.
He extended that diameter down the piece until further than the depth of the
box.
He used a Skew to turn the end to a point and at a slope that would leave the
cone shaped top reach full width below the lip of the box.
Paul sanded and decorated to match before parting off at a length that would leave the point just proud of the box,
Paul used the o'Donnell jaws to reverse mount the Lipstick and finish the
bottom.
The entire Lipstick was finally highly polished and placed in its box.
And the solution to the puzzle - blow it!
Providing there is a step down inside the lip of the box, a sharp puff will be
funnelled down the side of the lipstick and pneumatically raise it up and out.
The Sticky Ramrod
The punter is told of the importance of packing wadding tightly in a cannon and
that in Nelson's time, there was a device fitted to ensure the cannon would fire
its shot properly every time without misfiring. It used a rubber rope fitted
inside the barrel which the ramrod could hook up to and tamp the charge more
efficiently. Here is a scale model and this is how it works. The problem
was that only a skilled seamen could twist the ramrod the right way to make it
work. Let's see if you have what it takes to be a Master Gunner.
¤ The Cannon
Paul mounted a 5" x 1" block of Beech as above but supported with the tail stock
while turned to a cylinder.
With the tail stock withdrawn, the end was squared off with a shallow pointed
Skew.
The Jacobs Chuck was re-fitted and as the end cross-section was quite small, Paul elected to
start with a Centre Drill Bit before using an 8mm twist drill to bore a hole
almost to the end.
Paul turned the
outside to the shape of a ship's cannon.
A tiny hole was drilled on each side opposite each other just short of where the
internal bore ended so that a string of rubber could be threaded through and
glued at the holes.
The cannon was sanded, decorated and the back end (the Cascable) was
turned before it was parted
off.
¤ The Ramrod
A dense piece of Yew was mounted between his o'Donell Chuck and the tail centre to
make a stick in the shape of a ramrod.
Using a Roughing Gouge to start and a Parting Tool with an Outside Spring
Caliper for turning the diameter away with precision, Paul turned the blank to a
cylinder with 3 sections (evenly spaced out) having been carefully turned down
to just under 8mm but keeping a cylinder of wood at each end.
The Roughing Gouge was then used to turn away the wood between the 3 sections.
As the piece was getting quite thin, Paul rested one hand on top of the piece
immediately above where the gouge was cutting. This allowed him to lightly
press against the upward force of the gouge tip cutting the wood.
Each ramrod end was shaped as shown in the photo below before being well sanded and
parted off.
The distance between the cannon lip and the rubber was measured and a notch was
made on the ramrod at a position where it would engage with the rubber string
before the rod was fully in the barrel. Finally it was touched up all round as
necessary and highly polished.
And the solution to
the puzzle - it's like squeezing a slippery lemon pip.
The rubber string is a red herring - after the glue had hardened, a drill bit
was shoved up the bore and broke it so there is nothing for the notch to catch.
When the Puzzle Maker demonstrates his 'skill', he pulls the ramrod out as if it
had resistance and by subtly squeezing forefinger against thumb, the ramrod will
fly out of his fingers and smack back into the bore; all due to the end shape of
the ramrod.
The September Competition was set for a Puzzle or Trick incorporating elements of turned piece(s)
<to top>
June 2022 -
DEMO 2
Bird
Box
with Paul Reeves
You might have previously turned a Christmas Tree ornament in the shape of a
bird box, but to turn one of full size would waste a lot of wood, unless you
started with a log.
(click for close up view)
A good place to start is from the RSPB <here>
Leaving aside where and how to attach your bird box, some thought has to be
determined about external & internal sizes before mounting your chosen log.
Apparently, the rougher the finish, the better for the occupants.
Inside walls must be rough enough for chicks to grip when they try to go for
their first flight.
In times gone past, a perch was invariably incorporated but isn't any longer as
they tended to be perfect for predators to lay siege on the nesting tenants.
Paul had considered making a box out of staves and bound like a barrel but
decided upon a relatively straight log just over 6" in diameter. He had
started at home on a Graduate lathe because it was large enough to prepare the
body and roof with the log as a single piece.
If you have a smaller lathe similar to the size of the Club's, then you will
need to saw the log into the two component parts and prepare them separately.
Whichever method you use,
■
Mount the piece(s) between centres;
■
Leave one half of the roof section untouched to ensure that the bottom of the
roof will be bigger than the diameter of the body - this will allow the roof to
sit below the top of the body and avoid rain getting inside;
■
Create a spigot on the bottom of the body section and another spigot on
the top of the roof section to fit any reasonably large
and deep jaws that you have for your chuck.
Paul's Leylandii log had been a victim of February's Dudley & Eunice storms. It was
tight for the RSPB suggested dimensions but their sizes were suited for a
rectangular box whereas Paul's was for a circular box, which after all is a more
natural shape for a nest.
Shaping the Body
The body section was then mounted using the freshly turned spigot in the selected
sturdy jaws and the outside was trimmed up with a Roughing Gouge.
(click above for close up view)
Next, the centre was bored out with a Woodcut Pro Master Deep
Hollowing Tool which could secure Twist Drills Bits and Sawtooth Bits with grub
screws. Paul did try using a Sawtooth Bit initially with a toolrest
helping to start the central bore-hole accurately, but he found that it soon got
clogged with soft wet fibres so changed to a twist drill bit. Once the
central hole had been started, the toolrest was moved out of the way because the
rotating mounted piece kept the tool handle steady while the twist drill
progressed precisely down the spin axis centre. The hole
would eventually go through the entire body and out the bottom to act as a
drain but because of the limited length of the drill, this had to happen in
stages as the inside was hollowed.
The body was now ready to hollow out to the determined diameter & depth.
From the photo above :-
the top 2 are 'pick' tools which are easier to control but work rather slowly
because they produce small shavings;
the middle is a 'tip' tool which handles similarly as the pick tools but
slightly quicker;
the 4th is a Woodcut Pro Forme with the brass cap acting as a bevel;
and the bottom is a Rolly Munro articulated hollower. The bottom 2 do a much
quicker job but need practice to work efficiently.
There is one other option not shown above but had to be employed before these
specialised tools came along - a hefty Spindle Gouge used very gingerly and
taking a long time to complete the job.
Paul selected the Rolly Munro and started hollowing from the
centre outwards.
Ordinarily, one would aim to avoid producing vibrations and keep the cutter
running evenly to maintain a smooth finished surface, but the inside surface
needed to be a little rough, so hollowing out was progressed at pace.
Paul's technique was to have the tool handle pinned between his body and under
his arm while using his body weight rather than arm muscles to keep the tool
level with a consistent cut.
As the depth progressed, the ideal ratio of 5:1 either side of the toolrest
wasn't possible so his left hand needed a strong grip to hold the tool down onto
the rest.
Also, it was important not to lose the central hole. Because Paul hadn't
managed to breach the bottom of the piece earlier, he returned to his Twist
Drill Bit once he had hollowed out enough to allow the Woodcut Tool Handle to go inside the
body without touching the sides. Eventually, he managed to extend the central
bore right through the spigot to form the drain hole.
Knots can block the tool head with poorly cut shavings and need to be cleared
immediately as they prevent the cutting edge from working. He continued to
his planned depth and rounded off the inside floor like a natural nest. Having
checked for even thickness of the walls, he used a Spindle
Gouge on the outside and turn a curved bottom to match the inside shaping.
Having determined the size
and position of the hole as guided by the RSPB advice sheet, now would be a good
time to drill the entrance, although Paul had done this before the
demonstration.
(click above for close up view)
Shaping the Roof
This now allowed an opportunity to reverse turn the Bird Box
body and finish shaping it's rounded bottom.
With the roof still mounted and the body pressed into it's rebate by the tailstock
pressing against the newly drilled drain hole, you could turn away most of the the spigot and
shape the bottom of the body, before removing from the chuck and chiselling off the remnant
hollowed stub.
The roof was turned around and mounted into the newly cut expansion recess.
Top Tip : After cutting a
recess for an expansion dovetail, nearly tighten the jaws and hand turn the
piece - this will help clear out the bottom of the groove and allow the piece to
be held perfectly square.
The roof not only keeps the nest area dry;
it can also be designed to deter predators e.g. a spiked minaret!
Finishing the Outside
As recommended by the RSPB, apply any finish to the outside only.
Paul wanted to leave the roof as turned but disguise the body by 'scorching'
then using a Proxxon Long Neck Angle Grinder with a Carving Disc.
He used a blow torch to lightly blacken the body
(executed outside the Fire Exit in order to avoid setting off the Hall's
alarm!).
As the piece had to be removed from the lathe, a sensible precaution was to wear
an appropriate glove on his hand in front of the flame.
The Proxxon carving tool looks intimidating but isn't when handled with respect
and a bit of practice.
With the piece secured in the chuck, one hand held the
body of the grinder while the other hand remained on Paul's side of the
cutters, either switching the motor on/off or supporting the other hand or
rotating the chuck.
When switched on, the rotation of the cutters will be trying to move the grinder
away from your body.
Paul's technique was to just gently stroke the wood while pulling the grinder
towards himself using just the corners of the teeth to cut.
If this is your first attempt with a carving cutter, it is probably best to
practice on scrap wood before attempting on your hard worked piece. You might
find it helpful to control the motion of one hand by supporting it
with your other - rather than have both hands gripping the tool.
The first cuts Paul made were horizontal just below the entrance hole to give
something for birds to grip upon landing. He specifically made the horizontal
cuts angled downwards so any water would drop away rather than collect in the
groove.
The rest of the cuts were vertical.
The July Competition was set for a Bird Box turned piece(s).
<to top>
Natural Edge pieces rely upon the outside parts of the tree to improve the final look of the turned piece, whether it is by retaining the bark or stripping the outside edge to the Cambium Layer as seen in the Banana Bowl below. The latter's often unexpected shape is produced by turning a log 'end over end' as if you were making a two-bladed propeller.
An Unnatural Natural Edge is when the edge has been 'embellished' prior to turning the intended piece.
These shapes can be achieved by first turning between End-Grain centres (like a spindle) to create an outside shape, a tiny part of which will become the edges of the piece when subsequently turned 'end over end'.
Individual Method.
A log was turned into a cylinder and the
ends were squared off.
A pencil line was drawn down the length of the cylinder and its midpoint
circumference marked.
Top Tip : Now is an opportunity to draw
the pencil line so that any flaw on one side of the cylinder will be part of the
wood turned away from the finished piece.
Then the point 180° opposite was found using either the index of the
lathe/chuck; alternatively if your lathe hasn't any indexing, then by carefully
extending the pencil line through the end-grain centres and down the opposite
side so that the opposite centre will be found where this new line intersects
the previously drawn midpoint circumference.
With the cylinder still being
in/returned to its end-grain centres, a profile was turned into the sides.
Ideally, the shape should be a mirror image either side of the midpoint
circumference and avoid any sharp outward points as these are vulnerable to
breaking when turning end to end.
The shape was sanded through the grits as it will be the finished edge of the
final piece.
The piece was now mounted
between the end over end centres previously marked.
The photo below shows the planned outline for two spigots to be turned
The inside spigot (labelled ❶
in photo) is the first to be formed while between centres.
Then with that first spigot being mounted in a chuck (and if you feel necessary,
the opposite side being supported by the tailstock), turn away the outside to your desired shape while
creating the second spigot ❷
to where the base of the piece will be.
Top Tip : With the shape formed, sand
through the grits with a flat block held vertically so that it only touches the
wood perpendicular to its surface; this will ensure all leading edges will
remain crisp.
The piece was then reversed so that the base
spigot (labelled ❷
in photo) was now mounted in the chuck.
The piece was hollowed out to match the finished outside shape by carefully
maintaining an even thickness down the length of the profiled edge. Get
the thickness of the edges furthest from the centre accurate before progressing
inwards in order to maintain strength & integrity while working on the outer
wings.
Eventually, the inside spigot will be either turned away or shaped to
accommodate an embellishment (eg a candle holder; a box).
The inside surface should be HAND SANDED carefully to keep all edges crisp.
Reverse chuck to remove the remaining base spigot and to create a base/foot.
Pair Method.
Sometimes you will want to create a matching pair of intricate edged pieces.
This is easily accomplished with two identically sized rectangular blocks.
Paul's happened to have two 6" x 3" x 1½" Ash blocks, which he hot glued
together to result with a single square ended block of 6" x 3" x 3".
He then hot glued plywood squares marked so that they could be mounted exactly
on the centre line of the combined block before turning between centres to a
cylinder.
Then as above, a midpoint circumference was drawn followed by two opposite
points for the end over end centres, but this time, of course, both had to be
90° from the glued joint.
Again as above, your chosen profile
should be turned into the cylinder; avoid leaving sharp points (unless very
dense timber is used).
Sand to a finish before taking apart the ends and glue joint, and divide the
cylinder into an identical pair of rectangular blocks.
Once the centres of the resulting flat rectangular surfaces were marked, repeat the end over end turning guidance described above <click here to find>
Factors
to Consider
►Lathe speed
is important - the faster the better in order to decrease the time
the tool is turning 'air gaps' (although speed is limited by any imbalance of
the piece);
►Move the
tool in a controlled smooth curve and allow the rotation to do the cutting;
►Don't
press the bevel onto the wood - else you will end up pushing the
tool into the 'air gaps' and the leading edges will become damaged.
The May Competition was set for an Unnatural Natural Edge turned piece or matching pieces.
<to top>
MAY 2022
Revision of
Bowl Turning Techniques
with Paul Reeves
Thursday, 19th
May 22 at MWCC Club Night
It seems that the general public believe all woodturners are able to turn bowls so the expectations upon us are great. However, there is a lot to take into account before you even pick up a bowl blank.
POINTS TO CONSIDER :
■ Use of Bowl - Decoration normally
gives added value but best avoided if
to be used
with liquid / food as it will be difficult to keep any grooves clear and clean.
■ Material Choice - a Fruit Bowl can be made of almost anything because it's
not necessary to be food safe whereas a Salad Bowl is restricted to non-porous,
non-tainting & non-toxic woods. So avoid Ash /Laburnum / Padauk / Purpleheart
/ Yew
etc and
stick to woods like Maple / Beech / Sycamore / Tulip Wood / American Plane etc
that are considered to be food-safe.
■ Size & Shape - Deep will hold a lot but not ideal for holding delicate
objects heaped up on one another. Open like a platter is good for showing off
what is there but a high-sided or undercut bowl edge is better for tossing
salads.
Paul had selected a 7" by 3" Macrocarpa bowl
blank to highlight that although it can tear a lot when turned, with sharp
tools, a clean thin walled example can produce a sturdy bowl like the one he has used for years to keep
the
family's keys tidy.
Macrocarpa is a coniferous tree endemic to California
where it is known as Monterey Cypress and also prolific in New Zealand after
introduction in the mid 19th century. It is denser than most
pines and more resinous which gives off a smell for a long time before it dries
out. But once dried, it is very durable and holds shape well even when turned to
a thin walled vessel.
■ Mounting on Lathe -
Having decide which end would be the base after a look for figure / faults, he
mounted the piece on the lathe using a screw chuck. (An alternative could have
been between centres)
Because he was using a flat plate screw chuck held within jaws, he bevelled the
pre-drilled hole in the top surface to prevent any scurf created as the Screw
Chuck bit a thread into the blank, which could have prevented the piece from
being held flat against the chuck's plate.
■ Tail Stock - Whether to use a tail stock to help support the piece would depend upon how
big the blank was and whether you were going to take deep cuts like a 'Show
Pro'! This was a small blank and there was sufficient time to take
measured cuts so leaving the tail stock off allowed Paul better access to the
piece.
■ Choice of Gouge - A Bowl Gouge is the
obvious answer but how long should the handle be? If your drive head is
fixed and you are not using a Tail Stock, then a short handle is better in order
to avoid being hampered by the rails. However, some lathes have drive heads that
can be slid towards the end of the rails to emulate a short bed option, which
can accommodate long handles.
■ Choice of Cuts - The gouge can be used as
a 'Push Cut' (produces a clean bevel finish) or a 'Pull Cut' (results in
deeper/quicker removal and gets closer to the intended foot but gives a rougher finish).
A Pull Cut needs careful technique as only the radius of the curve and a little
of the wing should be in contact to generate a controllable cut. This is
achieved by presenting the bevel parallel to the wood surface with the flute
facing towards your left shoulder to ensure the wing is supported.
Providing your tool rest is close enough to the curved surface, you should be
able to start with a Pull Cut and by rolling the front radius of the gouge, you
can turn into a Push Cut within one smooth pass.
■ Plan the Foot - Don't let the chuck decide
the size of the foot. Big bowls need a foot outside a spigot for standard jaws.
The foot position will influence the chuck jaw mounting for hollowing with
regard to whether a 'compression' spigot (needs depth for a good grip) should be
created or an 'expansion' dovetail (reduced depth required but must have enough
wood strength outside the dovetail). You could decide upon no foot, but is
prone to rock. Once decided which jaws to use, set
your dividers to the appropriate size and remember when scoring the base, only
the LHS point touches the work - the RHS point must only touch air.
■ Squaring off Spigot/Dovetail - When
turning a bowl (except with an end grain bowl blank) there is often a problem
cutting across the end grains and ending up with fluffy strands which can hinder
the jaws from holding the piece centrally. Parting Tools and Skew Chisels
don't work as well as a small Spindle Gouge which will 'cut' the end grain
rather than scrape across them. A sharp gouge and moving the tip
slowly across the surface will also help.
■ Tools to Help Shaping - Shear Scraper
using a straight cutter for external and curved cutter for inside shaping. Lead
with the handle and angle the cutter against the wood surface away from being
horizontal.
■ Finishing - Mark the spigot's centre
point before detaching from the drive head to aid eventual reverse chucking removal. Sander Seal all
end grains and any tear-outs near faults before making your final pass with the
gouge. Try to move from start to end without stopping.
■ Decorations - Lines and marks can be made
with any SHARP pointy tool but avoid going too shallow as they might disappear
after sanding. Burnishing marks with wire tend to vary intensity when passed
over cross grain then end grain but Formica Burnishing is much better.
■ Abrasives - Beware getting your work
too hot while sanding with the piece turning. Some woods (eg Yew, Macrocarpa)
get hot from friction very quickly and can end up cracked. This danger is
reduced by slowing the lathe speed and by regularly keeping the abrasive clear
of dust build up with a wipe across a piece of carpet.
With the outside surface finished and sanded, Paul took the piece off the screw chuck and set up the chosen chuck jaws to grip the prepared spigot. He then squared off the face with a combination of pull & push cuts with the Bowl Gouge.
■ Shape of Inside - Lots of options
:- a small hollow in the centre; match the curve of the outside; curve the rim;
undercut the rim.
■ Direction of Cuts - For an Outside
Curve, cut from the axis of spin towards the outside. (NB: you often have to cut
a small area the other way in order to get a clean corner up to a spigot /
foot).
For an Inside Curve, cut inwards from the rim towards the axis of spin.
With a gouge with a swept-back grind, you have to steer the gouge tip above the
horizontal in order to avoid the metal bar of the gouge crashing into the rim but must steer back to end the cut at the spin axis. If
the bowl is particularly deep or has an inside curve with a sharp change of
direction, use a Bowl Gouge with a large bevelled angle (eg 70°) to help get a continuous
cut from rim to centre.
■ Tip Control - Be aware that until
the bevel can give support, the gouge tip has a tendency to slip outwards when
starting the cut. This is alleviated with a positive control of the gouge bar
where it lays on the tool rest and of the handle in your other hand.
As your cut moves towards the centre, the rate of the turning wood passing the
tool tip reduces so you should slow your movement as the tip gets closer to the
spin axis.
Try not to interrupt your cuts as it will spoil your 'muscle memory' for the
final cut. Make sure you have a sharp gouge before you start and get the
thickness of the bowl's wall uniform and accurate well before the last cuts.
There is an argument for making that last cut large rather than trying to skim
in one movement. This will lead to a cleaner cut and less angles to try to sand
out.
Angle the tool rest into the hollow to reduce the amount of gouge over-hanging
as it sweeps around the inside curve.
If the bowl is to be thin walled, work on getting the inner surface near the rim
close to the desired thickness before working further down the bowl. The extra
thickness in the bottom will discourage the thin walls from flexing during your
cuts.
With the inside sanded, it was time to reverse the piece in order to remove the spigot and finish the foot. The first thing Paul measured was the thickness at the bottom of the bowl. This confirmed how much of the spigot could be removed.
■ Reverse Chucks - There are
several ways to hold the piece for the next job.
Use an MDF faceplate with a groove cut into it to exactly fit the diameter of
the rim OR Press the piece against a flat faceplate while holding it
in place with the tail stock in the pockmark previously made when forming the
spigot OR Colejaws;
Whichever method is used, nibble the spigot away with a Spindle Gouge cutting
inwards towards the head stock - if you try cutting across, the same problem
with fluffy end grain will arise.
Paul had chosen to use Colejaws, so he protected the surface of
the rim with some masking tape before putting the piece in and tightening the
jaws.
Now that he knew how much he needed to remove from the base, he deliberately
left a pimple at the centre to give an accurate gauge of the depth removed and
then cut it away with the last cut.
<to top>
To achieve this, increase the lathe speed, then very VERY gingerly move the
narrow Parting Tool inwards so that it gently nicks the stubs. Stopping to draw
a pencil line along this new meridian will help to judge when your depth is
enough. Continue to gently part away until the pencil line almost disappears
before stopping and checking the depths where the meridians intersect. Repeat
until the intersections are of matching depths.
A Spindle Gouge can then be used to turn away any excess above the two
meridians. Move the tool rest so that the gouge bevel can touch the rotational
axis point or 'pole' where the surface will be perfectly level and therefore no
buffeting vibration will be sensed through the gouge when the lathe is turning.
However, once you move away and come across something higher than the meridians,
you will feel, hear (and possibly see) the tool buffet.
The next steps require precise and delicate control of the gouge tip.
Slide the bevel back sufficiently for the gouge tip to reach where the buffeting
started and allow the tip to just cut some dust; then carefully and steadily
move the tool forward to cut away a very thin layer; stopping if the tool starts
to run smoothly. Backtrack using the bevel and test for buffeting. Repeat the
delicate cutting until the buffeting dissipates. Smoothness can be assessed
with a light touch of the surface at the top of the piece with your thumb
pointing towards the direction of rotation.
Once this hemisphere is nearly even, a straight edged skew can be used to gently
smooth out any bumps sensed by your thumb, but keep the tool's contact moving at
all times.
When satisfied, slow the lathe speed down and briefly sand with abrasives. If
abrasives are used too much, there is a likelihood that more surface will be
removed on the side-grain than the cross-grain sides resulting in the sphere
appearing pointed.
The abrasive can be hand held or used with a flat block, but in both cases keep
the abrasive moving and parallel to the point of contact.
Next, the sphere was removed. It might require a mallet to tap the Cup Chuck in
the direction towards the head stock, but be ready to catch it when it pops out
with the first tap. (Do try to avoid hitting the sphere of course!)
The sphere is reversed to tackle the remaining hemisphere.
However, the Cup may be too large for the previously trimmed hemisphere so a
quick squaring off the face of the Cup Chuck as described above will narrow the
opening. Remember to check if the bottom of the hollow needs deepening.
Repeat as above to remove all the surface that is standing proud of the
meridians.
Short use of abrasive and your sphere will be complete.
<to top>
The basics of two part turning was covered in
Spindle & Face Plate Turned in January 2020 with a three-legged stool. <available HERE>
This demonstration is a Table Lamp with the added value of alternative
embellishments, e.g. Corian.
(Corian is a man-made mix of minerals and acrylic typically used in worktops and
can be turned on the lathe with a scraper.)
Top Tip : As synthetic materials tend not to move with
humidity, best to select dry wood for the wooden parts of the piece to avoid
loose joints when it inevitably shrinks inside a home.
Paul is using some surplus Corian-like material that had been
developed for aircraft interiors; however it can be worked the same as Corian.
The Knops.
Next he created a Jam Chuck from a cylindrical piece of gash wood such that one end could be secured in his chuck and the other end reduced using a Parting Tool so that it just fitted into the hole of the Corian and had a clean cut shoulder to hold the Corian perfectly square. He carefully made an accurate saw cut through the centre mark of the working end (down to well below the shoulder line) using a band saw or a tenon saw. With the the Jam Chuck attached to the head stock and the Corian ring set against the shoulder, the tail stock was tightened with its tapered point gradually parting either side of the saw cut until it jammed the Corian fixed onto his chuck.
Corian doesn't have any grain so it has no problem being scraped into a bead
with virtually any piece of well honed metal. The scraper works best with a
negative rake and by keeping it moving while at a slower lathe speed than when
turning wood.
Paul scraped one half of a bead and squared off down to the Jam Chuck on the
tail stock side of the piece before sanding. Corian sands well but does need the
lathe slowed even further while keeping the abrasive clear and cool by brushing
a carpet against the grit. He polished the surface to a shiny finish with some
0000 wire wool before reversing the Corian on the Jam Chuck and repeating for
the other half of the bead to match the first half so that both sides were flat
and parallel to each other.
The Well.
The outer edge was fashioned with an undercut
using a scraper as before.
The scraper was then worked from the highest point towards the centre following
the curve already made.
As seen in the intended profile above, the outer curved edge finishes at the
bottom of the material while the inner curved edge finishes higher up.
The desired shaped ring was cut with a parting tool straight into face of the
circular prepared piece.
The Base
Next, the internal diameter of the shaped Corian
ring (that was to form the Well) was measured and marked on the base.
A Parting Tool was used to carefully get the width exact for the ring to fit
snugly.
Once the ring's inner edge was right, the Parting Tool was used to deepen the
cut a little at a time until the ring's outer edge became flush with the base.
The Stem
Having turned the stem between centres to a cylinder of a size to allow for some
shaping by the finish, Paul changed the tail stock centre from a pointed tip to
a hollow ring type, which allows for a Shell Auger to be used through the tail
stock for boring a long hole up the centre for the electric cable.
With the stem re-mounted between these centres, Paul placed the point of the
Auger at about half way along the outside of the piece and marked the Auger with
a piece of sticky tape adjacent to the back end of the tail stock.
He started the lathe and fed the Auger through the back of the tail stock until
it eventually started to bore into the stem.
It now required a gentle steady feed with frequent withdrawals to clear the
waste sawdust in order to prevent the Auger going off centre. Once
deflected, you would never be able to correct it back on course.
Once the tape mark on the Auger reaches the back of the tail stock, Paul
stopped, changed the 4-prong drive centre for a Counterbore Drive, reversed and
remounted the piece for boring the rest with the Auger. Paul advised that
he could feel the Auger in his hand go soft just as it broke through the first
hole.
The hollow ring tail centre was replaced with the pointed tip centre and the
stem returned to between centres with the tail stock supporting the end destined
for the Lamp's base.
After setting his Spring Calipers to the size of the drilled hole in the base,
Paul used a Parting Tool to turn a spigot of appropriate length & diameter to
fit the base, remembering to account for the depth of the first Corian-like
embellishment he had turned.
He then continued to finish shaping the stem and added a shoulder plus another
Corian-like knop to go beneath the light bulb socket.
Paul had a brass insert that screwed
directly into the drilled hole of the stem. This insert couples the bulb socket
to the stem.
Top Tip
: If a
Lamp is going to be sold at some point there are some electrical goods
regulations that must be followed eg. cable clamp.
To avoid this problem, the simplest way is to sell it un-wired with the customer
arranging for a competent electrician to do so.
And finally, below all the parts individually and assembled with a coat of oil applied.
The February Competition was set for a two-part Table Lamp or Candlestick (base
and stem)
with "added value" eg colour, texture, other materials etc.
<to top>
The wood types best suited for box making have
moderately tight and even grain which won't present too many turning problems.
The tops & bottoms of boxes are better designed to be end grain; even so, softwood options will invariably tear out whereas
hard woods tend to cut cleanly.
Popular choices are from the Rosewood and Fruit wood families. Woods to avoid
have well spaced and well defined growth rings with fluffy open structured wood.
Likewise, some spalted woods should be avoided if the paler parts are
significantly softer than the rest.
Paul chose to turn a small box made from Box Wood adorned with the contrasting colour
of Pink Ivory to give a seasonal effect.
Box is an ideal wood for very thin walls and finishes beautifully with Carnauba
Wax applied.
Pink Ivory can provide a natural shine even from a tool finish.
For the sake of saving time during the
demonstration, Paul had prepared the Box blank between centres, turned the piece
into a cylinder of desired diameter with a spigot suitable for his chuck at
each end.
He had then parted the lid from the base at approximately
⅓ : ⅔ ratio.
[ Top Tip
: Before dividing your original piece into box
lid & box base, draw a pencil line along the cylindrical side so that once
separated, any blemishes in the wood can be quickly lined up].
Cabochon
(a smooth domed ornament; polished but unfaceted)
With the Pink Ivory secured in the jaws of his chuck, Paul used a broad parting
tool to turn a cylinder to a suitable diameter and depth to fit within the top
of the prepared lid.
A dome was formed on the front with a small negative rake scraper. Ordinarily, if done carefully (ie
with no scratches) there would be no need to sand. However, as Paul was going to
decorate using a chatter tool, the piece needed to start from a very shiny
finish for it to show up later between the chatter marks. He achieved this with
400 grit.
A chatter tool should only be used on end grain because applying to side grain
would result in marks of differing depths as the piece turned between the two
contrasting densities of along & across grains.
The chatter tool works because its end is sharp and flexible. Its effectiveness
is improved by slowing the lathe speed down a bit and presenting the tool tip
pointed slightly down.
When satisfied with the resulting design, the disc was parted off to the desired
depth and any pimple removed.
[ Top Tip
: If the box base is going to be hollowed out
with a Forstner bit, the above process can be repeated and adapted to produce a
matching thin disc for the inside bottom of the box to hide the centre dimple made by the Forstner ].
Decorative ring to go around spigot of box base.
Using hardwoods makes it easy to get a precise fit.
With the Pink Ivory still in the chuck, Paul used his parting tool to turn a
cylinder slightly larger than the diameter of the box base - this will allow a
clean precise cut-to-size later in the process when the base and lid are taped
together.
Having calculated a suitable diameter for the spigot, he carefully transferred a mark to the front of the Ivory using dividers.
The centre recess was
removed to a few millimetres deeper than the planned depth of this decorative
ring.
This could be started with a gouge or a Forstner drill bit in a Jacob's chuck or
(as Paul chose) with an old drill bit in a handle held against the centre of the
front as the lathe was turning. Whichever way was selected, the final cut to
the inside edge was completed with a Box Cutter to the mark made by the dividers earlier.
Paul parted off the ring and cleaned up the surfaces (that would be glued to the
base) carefully with fine abrasives for a close fit.
Spigot on base
for decorative ring.
Inside of lid to fit spigot.
Cabochon fitting.
Hollowing out base.
Paul changed his chuck for buffing mops, which he
used to smooth the surfaces with just the White Diamond compound. He feels that
the Tripoli compound with its red colour tends to darken the finish of the pale
Box Wood. Following a change of mops, he finished the buffing with Carnauba wax.
Don't put too much wax on the mop wheel as this can lead to a hard ring building
up, which will need wire wool to remove.
The technique for all the stages is a steady gently stroke of the piece
against the mop wheel and keep slowly turning it in your hands.
[ Top Tip
: spreading a folded towel or similar on the 'ways' underneath the mop wheel
helps to avoid dents if the spinning mop should rip the piece out of your hands ]
Pushing the piece hard onto or holding it still against the mop wheel will
result in a build up of heat which could distort the piece or burnish a flat
into the side.
Be warned - buffing a thin close grained wood to a magnificent sheen does make
the piece appear just like plastic.
(click either for close up view)
The January Competition was set for a box comprising of
2 or more contrasting woods.
Below are some more examples of Paul's boxes with contrasting woods for inspiration :-
The 'screw in ring stand' has a ring caddy
which slides up & down when inside the box but held steady by a screw thread
just below the brim.
The 'stud earrings box' has small holes for the stud pins and a central
container for the selection of ornaments to go on the studs.
The '2 cups inside' has one ring box with another lidded box on top, both having
a soft-close fit inside the outer box.
The 'dimple in lid' has a ring caddy that is the precise height to hold the top
of the caddy in place when the lid is on, which stops it rattling about.
(photos by
Rick Patrick & Paul Reeves)
<to
top>
November 2021 -
DEMO 3
Offset Turned Bowls
When is a bowl considered offset?
Take the three examples below.
The first has its bowl centre only slightly away from the centre of the rim of
the piece.
The second has its bowl positioned to avoid the natural voids and imperfections
(further enhanced with some piercing). [ Top Tip
: if you wish to pierce Yew, plan to do so with 'green' wood as Yew gets
very hard when old]
The last has a markedly offset bowl from the centre of the piece which has the
advantage of providing a large part of the rim available to decorate.
Note that with any offset, the piece will have a tendency to tip towards the
thicker denser edge and take up a natural 'show me' stance.
The slight offset example takes up this position but Paul has helped to maintain
it with a seat of soft rope with the strands at each end pulled apart to
stabilize the orientation (which he prefers rather than standing the piece on a
separate circular stand). The other two examples have thin rims and are
best displayed using plate stands.
Another important consideration is that when the
piece is centred on the offset, it will always be out of balance.
The more the offset (or wood removed in the pierced case) the greater the
imbalance.
Consequently, it is important to ensure the lathe speed is minimal BEFORE
starting to turn your piece in the offset position. Many lathes can only
change their speed with the drive rotating and it will be a bit late to realise
it is too fast when your lathe is shaking itself across the floor!
Although there are several Eccentric Chucks especially designed for offset turning, there is no need for such complicated chucks because a combination of a standard chuck with a Cup Chuck or a Screw Chuck can achieve the same results.
For best results, choose a blank with a decorative feature; eg burr, rippled, exotic or unusual wood. It could be first mounted either on a Faceplate or a Screw Chuck. Paul had chosen a spalted Ash bowl blank, which he mounted with its pre-drilled centre onto a Screw Chuck. [Top Tip : if your Screw Chuck extends from a flat plate, bevel the pre-drilled hole in the base; this prevents any scurf (from the Screw Chuck as it bites into the piece) protruding and preventing the piece from being held flat against the chuck's plate] Ensure that your pilot hole is just the length of the Screw so that it will later disappear when gouging out what will become the inside of the bowl.
As with last month's 'Turning a Plate' demo, you could use just 1 tool to make this project; eg a 1/2" spindle gouge or a small bowl gouge. Turn the the back to a curve of your choice; eg hemispherical, conical, parabolic shape. Sand to a final finish (see Principles' below) then seal with Sanding Sealer, wiping off any excess. Pay particularly attention to sealing the end grain in order to prevent hot glue from penetrating deeply down the grain in the next step.
Sanding PrinciplesPaul chose to create a Cup Chuck connected to the
driven chuck via a Faceplate. The advantage being that with the outside
already completed, he only had to finish the piece mounted while glued to the
Cup Chuck without the chore of reverse chucking to remove a spigot.
The Cup Chuck was made from waste wood or an old bowl blank of about 6" by 2".
A faceplate to fit the chuck was screwed on centrally and mounted in the
standard chuck. The screws had to be reasonably short to avoid any chance
of their ends breaking through the depression being gouged from the other side.
Consequently, he made use of all 6 screw holes. The depression was planned
to match the curve of the piece and as deep as possible
without the Faceplate screws penetrating the bottom, even after the Faceplate
was later offset.
Once satisfied with the fit and remembering to try and avoid the two end grains,
Paul started to hot glue by holding the piece to the chuck (gauging carefully by
eye that the flat surface was sitting perpendicular to the axis both up & down
and side to side). He dropped the glue onto the Cup Chuck so that it
flowed down into the V-shape and made contact with the piece over about an inch.
Patiently allowing a couple of minutes for the glue to set, he rotated the whole assembly
about 60° and repeated another five times.
[Top Tip : Use polythene glue sticks rather than
other general purpose sticks because after polythene glue cools, it can easily
be removed by warming with a hot hair dryer and being 'thumb rolled' off
]
Once all the glue had hardened, the face was flattened off with a
gouge. [Top Tip : It is easier to achieve
an accurate flat surface by keeping your elbows to your side and rock your whole
body forward rather than attempting with out-stretched arms.]
The level face was sanded and sealed as above.
Then the LATHE SPEED WAS REDUCED to minimum because the next step was to offset.
The entire Faceplate, Cup Chuck and piece was removed as one
section.
The Faceplate was unscrewed, repositioned 10mm offset and re-screwed.
Paul recommended that a 15mm offset be considered the maximum because 15mm would
result in the bowl rim max and min differing by 30mm and any larger could
restrict your options of the eventual diameter of the bowl.
With the piece now offset, it will be unbalanced and would
benefit from counterbalancing.
Paul had a size variety of lead flashing pieces to choose from.
The side of the Cup Chuck that was nearest to the lathe's spindle centre (to
compensate for the wood that was there on the opposite side) was where he used
two screws to secure the lead.
In his experience of harmonic vibrations, Paul reports that one can expect to
gently increase speed through the first vibration which will eventually settle
down, but as one slowly increases speed towards the start of a second vibration,
immediately back off the lathe speed a little.
The faster the pieces turns, the cleaner the cut so finding the right lead
weight to reduce vibration and increase turning speed, the better.
Paul turned out the inside of the bowl using a prepared card
shaped to the desired profile to guide where and how much to remove.
Further decoration was considered. With a flat surface with an offset hole, a
plain wood might be worth accenting with a defining point, eg a small cove at
the bowl rim. This might not suit for some figured or spalted wood.
The consensus of those present opted for no further decoration as the spalted
Ash was decoration enough.
The piece was sanded as before. After thorough brushing out, it was sealed
again.
A hair dryer was used to gently warm the glue so that it could be carefully removed to free the piece from the Cup Chuck. Note : It's important not to overheat woods (eg. like Yew, Cherry, Macrocarpa) or else there is a danger of causing surface crazing.
The December Competition was set for a turned example of an offset bowl.
<Competition Results>
(photos by
Graham
Turner, Rick Patrick & Paul Reeves)
<to top>
October 2021 -
DEMO 2
Turning Plates & Platters
What's the difference between a plate, a platter and a shallow bowl?
In Paul's humble opinion, you need to apply the
Turning a Plate
When taking out the central waste wood, it's a good idea to purposely leave a
pimple in the centre. If this is done from the first indent cut, it will give a
precise indication of how deep your last pass went and help avoid the platter
bottom getting too thin.
Check for levelness with a ruler (if there is room) or else with a short block of
wood you are confident is flat.
Shave off the pimple just before the final cut.
With the lathe at rest, start sanding along the grain using a fresh/new piece of abrasive
supported with a block to flatten out the inevitable
irregularities. Then, with the lathe speed much reduced (to avoid excess heat
and clogging the abrasive), sand while keeping the block moving. Should the
abrasive ever be held still with the lathe turning, it is inevitable for scratch
circles to appear in the piece.
Work through the grits (changing turn direction if available) and after every
other grit, switch the lathe off and finish by hand along the grain.
To finish the back, remove the Ring/MDF and reverse the piece into cole jaws or
whatever your preferred method of reverse turning.
If you used hot glue, be careful with any remaining traces as it can be quite
'grabby'.
A gentle pull cut normally clears the surface well.
If no foot is planned, level off remembering to slow the gouge head movement
nearing the centre.
Cross check with a ruler although a marginal central dip would be acceptable.
If a foot is planned then proceed as you did with the front indentation.
Use abrasives as described above.
Turning a
Platter
Using a test piece of Ash (his chosen wood for this piece), Paul had compared
two ways of ebonising in readiness for decorating; that is by 'burning' or by
spraying 'lacquer'. Paul found that burning resulted in the Ash bleeding some of the
surface black down into the wood resulting in a muddy finish when he cut through
to the underneath. However, the sprayed surface showed a sharp contrast when
cut, particularly with his pale Ash.
The platter's rim was shaped and sanded much as for the plate above.
The outer edge was ebonized with the spray while the centre wood was still in
place, in order to prevent overspray getting onto a finished surface.
The chosen pattern was applied using a Proxxon V-shaped carving gouge to create
grooves - this method is a lot quicker and produces a smoother finish rather than trying to
manually cut grooves with a mallet and chisel.
The round flower centres were produced with a ball carbide cutter in a Dremel.
The leaves and flowers were painted on with a small flat brush.
Paul used Jo Sonja's iridescent paints (other producers : Chestnut, Arteza,
Pebeo) which become vivid colours when against a dark background.
But be warned, when squeezed out onto a pale surface, all the colours will look
unbelievably identical creamy splodges. So do make sure you remember/label each
splodge with its actual colour. Also, very little is needed to cover a lot. On
the night, Paul found he had wasted more than he had used.
Finally, the solid colour of the flower centre was a yellow acrylic.
It took at least 20 minutes for all the paints to dry sufficiently for a coat of
clear acrylic gloss lacquer to be applied to seal and protect the decoration.
After being left to dry overnight, the platter's waste wood and back was turned
and finished as described above for the plate.
The Octomber Competition was set for a turned example of a plate or platter.
(
photos by Mark Codling & Paul Reeves)
SEPTEMBER
2021
-
DEMO
1
Treen Hand-Held Mirror
with
Paul Reeves
Thursday, 16th September 2021 at MWCC Club Night
Treen is a generic name for
small - handmade -
functional - household object - made of wood.
Treen is the 'Old English' word for "of the tree" and used by all until 'mass
production' brought about lower prices and gradually, modern wood alternatives.
Old treen tends to be obvious from a look underneath the piece. To earn a
living, the carver/turner had to work so quickly that very little of what's not
seen ever got touched. Speed of production usually meant the worker didn't need
many gouges. Nowadays, production is invariably for the pleasure of working wood
and the creative satisfaction of making something useful.
'Treenware' covers a multitude of sins. Toys, tools, moulds, practical or
humorous gadgets etc; but treen is distinct from furniture making.
Below are a few examples :
For the demonstration, Paul elected to turn a 4" Hand-Held Mirror out of Yew in two parts; ie the mirror surround being face plate turned and the handle being spindle turned.
As the mirror surround was to be
decorative on both faces, Paul wanted to avoid any chuck recesses. An
approximately 6" diameter by ¾" thick round
of Yew with an attractive grain was prepared with a hole in the edge to receive
the handle spindle (this procedure needed care to get the hole drilled precisely
lined up centrally). It was then carpet taped to a base plate to fit the chuck.
A parting tool was used to mark the exact width of the mirror before taking out
the centre leaving a flat surface for where the edge of the mirror could be
glued. The rest of the centre was carefully removed to over half depth (to
reduce the final weight) but would still allow the back face to be about 4 or
5mm thick when finished.
Paul commented that using small tools for this job was a good way to improve
one's gouge technique as lots of small cuts are needed.
The outer edge of the surround was shaped keeping in mind the need to copy that
same shape from the other face.
Paul highlighted that when using abrasives or buffing Yew pieces, they are prone
to getting too hot very quickly, which would lead to cracking or splitting. This
is avoided by reducing downward pressure; regularly clearing the dust off your
abrasive (eg with a small piece of carpet); dusting off between grits using a
brush or tack cloth.
The face was then treated with sander sealer prior to decorating with a
texturing tool and wax filler. (Various texturing techniques are to be found
in the Archive
<HERE>)
Paul had decided to use his Decorating Elf with a
Ball Cutter and gold paste wax/gilt cream to in-fill.
The Elf was used to apply crisp surface cuts to reach beneath the sander sealer.
The patterns were subsequently framed within outline indents and a
burnishing/bronze wired brush applied to remove the fibres thrown up by the
cutter.
A generous coat of embellishing paste was applied evenly over the textured areas
and allowed to dry a bit before the excess was removed. Paul first used a
paper wipe moistened with white spirits to loosen the paste before using a clean
paper wipe across the line of indents. If this had been wiped along the
indents, it would likely remove most of the paste.
(click 'Front Face' for close up view)
The surround was removed from its base plate and the current depth in the middle was measured to plan how many millimetres the back face needed to have removed to leave a 4 to 5mm wall thickness. The piece now needed to be mounted for the back face to be completed. The simplest method would have been to use a chuck to expand against the mirror rim, but the available chuck was not large enough so the base plate was adapted as a Jam Chuck by turning out a spigot that just fitted the mirror rim and secured with a few daubs of hot glue.
Once the glue had hardened, the back face was turned
away to the calculated wall thickness followed by the outer edge made to match
its opposite side. Abrasives were used along the grain with the same
precautions of dealing with Yew wood as above. Sander sealer applied and the
piece decorated in sympathy with the front face.
An appropriately sized spindle handle was fashioned & decorated as above before
gluing into the hole originally prepared in the mirror surround.
(photos by Mark Codling, Rick Patrick & Paul Reeves)
The September Competition was set for a
turned example of piece(s) of treen.
<to top>
January
2020
- Demo 5
Spindle & Face Plate Turned
This Competition is to create a piece which
combines spindle driven work with face plate / chuck driven work.
This invariably results in two (or more) pieces of wood turned separately and
finish up joined together.
Effectively, some will be turned along the grain, the rest will be turned across
the grain.
This makes for a very broad range of
designs.
Below are a few examples :
For the demonstration, Paul elected to turn a
three-legged stool out of well-dried spalted Beech; ie the legs being spindle turned and the seat being face
plate turned.
A
roughly rounded seat had been band sawed from a plank and 5 blobs of hot glue
were used to attach a MDF face plate to the intended seat top. The MDF had been
prepared with a shaped hole to fit chuck jaws under expansion which allowed the
roughed-out seat edge to be rounded out, the under-seat squared off and mortise
centres carefully drawn at 120° to each other about 2" in from the edge. (If
these were inaccurate, when the mortises were being drilled at about 12½° inward
incline, the seat would not have been level). The underside was also hollowed
out to fit expanding jaws for turning the upper surface but leaving enough
centre wood to support a tailstock for finishing the underside.
Paul explained that he liked stool leg tenons to go about an inch into their mortise; but without some trickery, this would make the seat look very heavy. The deception is achieved by bevelling/coving the under-edge to leave enough thickness for the leg sockets. Weight can be further reduced by hollowing out underneath between the legs.
After the underside had been sanded
with the lathe on, followed by sanding along the grain with the lathe off
through the various grits, the MDF plate was prized off and the worst of the hot
glue removed by hand before being remounted in the chuck to work on the seat
upper surface.
If using a gouge to remove the last of the glue, be aware that a push cut can
result in a 'dig in' as the glue residue might snag the tool tip. A better
method would be to use a pull shear cut.
Now a decision has to be made; are
we making a side table (needing a flat top) or a stool (with a slight dimple to
improve comfort)?
This was to be a stool so a gouge rounded off the top outer edge to prevent a
sharp edge under the sitter's thigh; and a gentle indent was turned.
The top was finished by sanding through the various grits, stopping to sand
along the grain, inspecting, brushing all dust off before reversing the lathe
direction with the next grit.
The piece now had to be remounted in
either cole jaws or else between a tailstock and a grip pad up against an MDF
face plate. This allowed removing the chuck jaw bevels and to finish hollowing out
the centre of the underside.
Care must be taken with regard to how deep to hollow out. Beech does not turn
well when thin!
It was now time for spindle turning.
With 3 identical legs to produce, it is helpful to make a 'story stick'
using a piece of wood with nails (or holes for an awl to poke through) to
delineate the overall length and where significant highs or lows will be on the
finished piece. Paul favours a small rectangular stick with appropriate
drilled holes for an awl to make an accurate mark when placed upon the tool rest
while against the mounted wood.
His design for these legs was a baseball bat shape with a hemispherical foot and a simple straight taper into the tenon, without leaving a shoulder (which would be difficult to achieve without appearing unsightly at the inclined joint between leg and seat). Tonight's legs just needed a Story Stick with a bottom end where the foot starts, a start point for the half round foot, a start point for the tenon and an end point of the tenon.
Having marked his spindle, Paul explained he found that a slightly oversized spigot is better formed at the tailstock end using a parting tool. He then angled his long tool rest to parallel the hemisphere start and the tenon start marks as a useful guide for the required taper to fade into the tenon. When trimming down the taper with the tool rest at an equal distance, remember the need to gradually lift the gouge handle as the leg's diameter gets smaller.
In order to leave room for glue, Paul finished off
the tenon to a loose fit with a chamfer to aid assembly.
Traditionally, a bus ticket was used to take up the slack on an old stool where
the legs had shrunk with age or use, for example, in the milk parlour!
(photos by Mark Codling, Ian Wright & Paul Reeves)
The January Competition was set for a
turned piece(s) comprising of a combination of cross-grain with
along-grain turning in each completed piece.
<to top>
Paul Reeves
Demonstration of Off-Centre Turning
Thu, 20th February 2020 at MWCC Club Night
Eccentric turning can produce elegant and aesthetically
pleasing pieces, for example :-
Polygon Shaped Spindles
Twisted Shaped Spindles
Oval Tool Handles
Cabriole Leg
Both ends of the work piece were marked out with a
centre-point and straight lines joining the centres (not the corners) of
opposite sides.
Then a circle is drawn such that where it crosses the straight lines, these
become the contact points for the drive & tail centres.
Care must be taken to ensure they are not too close to the edge of the finished
piece or else the centres will not have enough grip to support.
With a compass centred on these four new points, draw arcs of the same radius to
guide where the final edges will end up.
(The greater the radius, the more pronounced the angles at the corners will
be)
Finally, number the four arc centres of one end (1 - 4) clockwise and once
you've identified the corresponding number 1 on the opposite end, number these
arc centres anticlockwise!
It will save quite a muddle later on.
Ensure the lathe speed is set low and any tool rest is
well out of the way before mounting the work piece.
Using
● a Spring Steb DRIVE Centre &
● a Spring Steb or Revolving Ring TAIL Centre,
mount the work piece onto the lathe with drive & tail points on the arc centres
marked 1.
The work will be offset so check that it clears the tool
rest when the piece is rotated by hand.
With it out of balance you need to carefully adjust the lathe speed up until
just before vibration starts to intensify.
Remember to stop the lathe if you need to readjust the tool rest.
Smoothly take off the one side with a roughing gouge.
(It's important not to push the gouge into the piece; just along the piece
with the handle down to keep the cut gentle)
Check for a level surface as you turn away down to near the final edge marks drawn on
the ends.
Sand using abrasives on a block just gently kissing as the lathe slowly turns.
Finish off each grit along the grain with the lathe stopped.
Repeat with centres marked 2, 3 and 4.
You might need to re-mount some of the centres to trim faces straight, even &
level.
The ends were marked out as above with the sole exception that once one end
is marked 1 to 4, the corresponding number 1 on the other end must be one hole
further round.
Once again, one end must be marked 1 - 4 clockwise while the other end marked
anticlockwise.
Thereafter, work as above to smoothly turn off each side.
With eccentric turning, speed is your friend because the untouched section moves
pass the gouge tip quicker so there is less tendency for the gouge to 'fall
inwards' before the touched side comes around again.
A shadow will appear at the top of the piece; you should work to get that shadow
parallel to the lathe beam.
Sanding with the lathe stopped may be more effective with applying the grits
along the grain.
You might need to re-mount some of the centres to trim faces evenly.
The
reduced curves of the flatter faces will need a larger radius than the radius
used from the centre of the work piece.
This may cause the offset centres to be near or even outside the finished cut.
Consequently, both ends of the work piece must be left uncut with enough length
to ensure there is sufficient strength to support the drive & tail centres.
Remember to allow for this when selecting work piece length.
Marking up in this case benefits from drawing straight lines from the
diagonals (to find the overall centre); draw a circle (which will
become the widest dimension).
Then mark 2 arc centres equidistant from the work piece centre such that the
drive & tail centres will have enough support up into the corner of the piece.
Draw in the arcs within the previous circle (to guide where the final edges
will end up).
Take care that your centre marks on the other end correspond to the same
diagonal!
The piece was mounted between centres and a parting tool used to delineate
the ends of the finished handle to the depth of the widest dimension.
With a roughing gouge, a cylinder was formed to include any shaping required (eg
curves for a handgrip) using the parting tool depth marks as a guide to the
minimum size to turn away.
The cylinder was sanded through the grits.
The parting tool was then used again to reduce the spigot end-delineations to
the depth of the guide arc on the end of the piece.
It was now mounted using the offset centres.
The same principles of tool rest positioning, lathe speed and smooth tool use
were applied as highlighted above.
The newly reduced sized spigots showing up in the shadow of the turning piece
now acted as a guide to how much to turn away each face.
The piece was sanded using abrasives on a block just gently kissing as the lathe
slowly turned;
each grit finished off along the grain with the lathe stopped.
Then repeated using the other offset centres.
Be prepared to re-mount to one/both of the offset centres to get the faces even.
First, we need to think of what happens when we offset in opposite directions
from the overall centre.
Imagine a block of wood revolving and the shadow resulting will resemble the
drawings here.
In figure 1, the amount of opposite offset at either end is the same;
In figure 2, there is a larger offset at the bottom.
The red line defines where there is no shadow and the piece appears stationary.
For want of a better name of something on a leg, let's call this the 'knee'.
You can see that the greater the difference in offsets at each end, the 'knee'
moves closer towards the smaller offset end.
When turned away from the knee downwards, this will produce an elegant shape for
a cabriole leg.
Whether the cabriole leg is for a seat or table top, its helpful to leave the
top few inches as a square to aid attachment.
Feet are traditionally set on the diagonal so they face part forward and part
outwards & look more stable.
Marking up the ends involves drawing in the diagonals to find the overall
centre.
A very small offset should be marked on the top but on the bottom end, mark a
larger offset on the same diagonal but the opposite side of the overall centre.
Remember to make a note of these offset distances for making matching legs.
Mounted between overall centres, Paul used a skew to cut a 'V' about 2" from
the planned top end and deep enough to mark all four edges.
A roughing gouge turned away a cylinder from the 'V' cut down to the bottom end.
A bead was formed with a skew, spindle gouge or beading tool to tidy the V under
the top square.
The planned bottom end was marked out for :-
● where the leg would touch the floor,
● widest part of the bead that the foot would stand on,
● widest part of the foot.
The piece was mounted between offset centres.
Working from the 'knee' towards the bottom, Paul turned away the shadow as far
down as the widest foot pencil mark.
The piece was reverted back to centrally mounted to form the foot and the floor
bead immediately below it.
The foot area and the knee areas were sanded as described previously.
Then while mounted between the offset centres, the knee to foot areas were
sanded.
(photos by Mark Codling) <to top>
Podlets are a name generally given to small
thin wooden flower-like structures.
The choicest wood to select is wet/green, is of reasonable
length to enable a degree of bend of the stalk; most with light or dark colours
work well. Natural edges look fine but it would not be a problem if
all/some is missing (as explained below).
Another consideration is that the base be heavy enough to stably support the
finished piece.
Bear in mind :-
● The piece will start off being supported between centres and that both ends
will need to be squared off.
● The roundest end is better for the petal & supported in the tailstock; the
drive end will eventually be trimmed as per your chuck spigot for supporting
while hollowing out
the petal and turning the stalk.
● Ideally, for strength reasons, you want to avoid the pith anywhere inside the
finished stalk. Choosing a piece with an off-centred pith (eg horizontal branch
with a large area of reaction wood above) would be ideal but otherwise,
purposely plan to offset the centres such that the pith lies about 10mm from the
stalk and so will end up being cut away.
● The tailstock will be removed for hollowing the petal but needs to support the
piece when turning the stalk;
so a ring or cone live revolving centre would be the best to use.
While in between centres, start off at a slow
turning speed as the piece will probably be out of balance.
Keeping the bark on the top end of the petal, even off the rest of the piece, which will
gradually allow you to up the speed.
Start a shallow hollowing of the petal & form a spigot for your chuck at the
drive end.
Mount on your chuck & continue hollowing with a smaller gouge (to avoid
excessive vibration without the support of the tailstock) to a depth of at least
an inch.
Once the inside is completed, finish with
abrasives before continuing with the stalk & base.
Wet/Green wood tends to become fluffy and clogs the abrasive - problem reduced
with wet sanding (i.e. dip abrasive into water)
Tailstock now returned into position but with
some matting material to protect the contact area within the petal.
Trim back the bark towards the lip of the petal; if one side of the lip ends up
too thick (perhaps due to avoiding the pith), an option is to reduce the
protruding edge back into the round and then decorate the edge with a
pyrographic tip.
Working towards the headstock about an inch
at a time, turn out the stalk and sand finish as you work along while the
strength of the piece is supported from the drive end. John used a
homemade Velcro-ed piece of plywood with various grits in order to even out the
stalk as he progressed, making sure (where the stalk was particularly thin) to
support the opposite side with his fingers.
Plan ahead where the piece will be parted off
and thus where the start of the base should be.
The piece will look better with the base being a smaller diameter than the
petal.
Reduce the base to desired diameter and shape to blend the curves.
Wet wood will naturally dry out and distort
the piece.
For a more controlled process, one can microwave the piece with a heavy
microwave-safe mug/bowl resting on the stalk.
After the one time he tried this method & the lady in the house expressed
concerns of smells from the kitchen, John now uses steam from a kettle on a gas
ring applied for about 4 or 5 minutes via a hose with a split in one end.
There is a helpful video on line <HERE>
<to top>
Paul Reeves
Demonstration of Texturing
Thu, 21st November 2019 at MWCC Club Night
Putting on Texture improves a plain grain wood with contrast. For example, applying a band of indentations about an inch below the outside rim of a bowl (where one's hands will invariably grip the piece) adds to the enjoyment.
There are four ways of applying texture :
● Both held tool and piece stationary;
● With the piece turning and a simple tool on the tool rest;
● Using a rotary tool with the piece held still;
● With the piece turning and using a rotary tool.
It is not necessary to have lots of texturing tools.
Simple Tools include :
Ball Pein Hammer
Straight Metal Bar with a domed head (Tip: avoid any
with sharp edges)
Hole Punch (Tip: smaller punches
make colour tints look better)
40 Grit Abrasive! (Tip: but keep it moving)
More Sophisticated Hand Tools :
Thread Chaser
Chatter Tool
Coarse Hand Knurl
Sorby Texturing & Spiralling Tools
Henry Taylor Decorating Elf
Power Tools include :
Angle Grinder (eg Proxxon)
Electric Drill (eg Dremel)
Power Carver
Techniques :
A change of the lathe speed will result in different effects. With powered tools, the higher the lathe speed, the less regular the texturing while with the piece turning slowly or stationary, the cleaner the effect. The opposite applies with the speed of the cutting tool - the faster the speed of the drill, normally the neater the finish.
A common decorative texture is Fluting.
These are best created using powered tools with accessories such as Ball Cutter,
Chain Cutter, Flat Disc or Power Carver.
If applied with the lathe turning - present the tool in line to the rotation of
the piece.
If applied with the lathe off - move the tool in the direction against the
cutter's rotation.
The Power Carver tends to produce the smoothest fluting.
Once your texturing has been applied, you will probably need to tidy up the
edges and clear away the 'hairy' bits.
Whether using a bristle brush by hand or a rotary tool with a brush attachment,
move the brush in the same direction as the line of pattern.
A Blow Torch can be used to burn off hairy bits but should only be used if
leaving as burnt decoration or if colouring with something which will cover up
the inevitable scorch marks.
(photos by Mark Codling) <to top>
August 2019 - Demo 3
The September 2019 Competition was set for a turned piece(s) comprising at least 50% of a ply component.
<to top>
October
2019 - Demo 4
Handles & Feet
with
Graham Turner
Handles & feet on wood-turned pieces benefit from being curved
themselves.
Apart from carving, which is not a technique many woodturners have mastered, the
Turner's solutions were twofold :-
Either
turning a hollow form, then band-sawing into segments to produce several
identical pieces;
or
(taking a leaf out of the last demonstration with Ed Walker), creating a
laminated piece and steaming into shape against a prepared shape former.
A practical wood for steaming is Ash. Graham had built up
laminates from 2.5mm Ash veneers (referred to as Constructional Veneers)
interspersed with 0.7mm Wenge veneer for contrasting colour.
Photos 2 & 3 below demonstrate two differently shaped formers.
Both produce flattened curves, but if desired, could be mounted between centres
and their side edges rounded off.
Graham's example was a flat offset base (as in photo 3) with a cylindrical
handle subsequently rounded off between its centres (as in photo 4).
Great care must be taken to ensure the flat base doesn't foul the tail stock
while turning the handle.
The turner's fingers are also vulnerable so Graham prefers to put his guiding
hand under his gouge rather than over the tool rest.
Steaming was accomplished in Mrs Turner's Vegetable Steamer for
about 5 minutes immediately before bending and clamping against it's shape
former.
(It wasn't made clear whether Mrs Turner was aware of this usage but Graham did
wash it out afterwards; so that will be all right then!)
Graham then demonstrated a method for producing feet for a
piece.
Always enjoying humour in his turning, Graham took the literal sense of feet.
Starting with a piece of Walnut with a hole through one end using a 25mm
Forstner, he turned a lip at the tail end before hollowing out to leave about a
10mm thick wall, (photos 5 & 6).
Using an indexed chuck to delineate every 30
Each 'foot' was placed between a ring drive centre (for better drive support) & tail stock to shape the leg
muscle
A microplane was used to round off the toe & heel areas before back to the
bandsaw in order to form individual toes, (photo 9)
A similar process can be employed for making handles that connect at both ends.
Photo 10 shows the various stages.
With careful design, this system allows for the connecting ends to line up flush
with the outside of your turned hollowed vessel to help with a larger gluing
surface.
It is important to consider the direction of the wood grain in order to preserve
strength.
Handles designed with large curves are likely to have a weak section of end
grain somewhere while shallow curved handles with grain from one end to the
other will have more integral strength.
Choice of close grain woods like Walnut, Maple also contribute to strength.
<to top>