Pro Demo

January 2024
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.

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.


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.

<Competition Results

(photos by Rick Patrick, Andy Ogilvie & Ian Wright)