Model Engine Works: 009 Tattoo Class 0 4 2

A venture into white metal kit building.

The Kerr Stuart “Tattoo Class” is a favourite of mine and I have built quite a few models based around this type of engine. They were built by Kerr Stuart & Co in large numbers at the beginning of the 1900’s as a small workhorse engine, the majority being for 2 ft gauge lines and having outside frames, to accommodate the firebox. There were however quite a few built for wider gauges 2ft 6” and 3ft with inside frames. Being a basic engine, most had open cabs, though some had enclosed cabs added in different forms at the time of manufacture, or later by their owners.

A Christmas gift I once received was a white metal version of the Talyllyn Railway’s engine Edward Thomas. I had also had an Ndrive Productions 0 4 0 Chassis which was a suitable size to fit the kit, needing only the addition of a rear pony wheel. The spark that prompted me to finally build the model was a holiday in mid Wales, where I planned to visit the Talyllyn Railway and perhaps see Edward Thomas in person.

I started by looking for the right candidate for a pony wheel, which needed to be around 5.3 mm. There was also the question of how to mount the wheel onto the chassis. Now Ndrive Productions (Neville) has a nifty little etched universal mount to do this job, a cross with several holes to fit the wheels and create a pivot. The only thing was that you needed a wheel set that separates from the axles (to pass through the holes in the pony truck etch).

I discovered that the Kato wheel sets are held together with a plastic tube (to electrically insulate the wheels) and are close to the right size for the pony wheel. By filing off the pinpoint bearing and carefully opening out the hole in the etch I had a basic pony wheel and mount. Having selected the suitable pivot hole on the etch, it was then a fiddly job to drill a small very accurate hole to take a 10 BA cheese head machine screw in the base of the chassis. Care is needed as you are working very close to the gears, (so don’t slip)?

This pony wheel assembly is very light and does not ride on the track well in reverse, although its wheels are free moving and it pivots easily. The etch being a cross shaped form does give the opportunity to add a little weight at the back of the wheels. The 10 BA cheese head needed to be filed down to a thin disk with a new slot cut across it, to avoid catching on the track at points. It was also necessary to file down the wheel pick-ups at the back of the chassis or the etch for the pony wheel would not pass over these.

The other areas of the chassis that needed to be fettled were above and in front the cylinders. These needed to be filed off and cut to allow the chassis to sit tightly up to the underside of the footplate. Also, the width of the rear bar needed reducing at both sides.

To say that this kit was designed for another type of chassis, it was a surprisingly good fit. There was a small area for the cab front and underside of the boiler to remove to accommodate the slightly bigger motor, a few tweaks to the footplate at the front a small square to cut out for the worm gear, and that was it. The body and the chassis were held together by forming a small L shaped bracket at the back and glueing this to the underside of the cab, this formed a channel for the rear of the chassis to hook into.

The front fixing of the bodywork uses the existing counter-sunk machine screw and nut supplied with the chassis. This was done by slightly deepening the counter sink in the chassis and glueing the nut to the top face of the footplate situated above the existing hole. All of this was done before the bulk of the model was put together. I also added the blast under the saddle tank and in the smoke box before final assembly. It needed more weight at the front to counter the overhang of the cab, and partly to reduce this weight. I did not use the cab roof since this appeared too thick and bulky ,but instead formed one in Plasticard sheet, creating the gutters which the metal roof lacked.

Other modifications to the model included adding brass 0.45 mm wire handrails to the cab sides and above the smoke box. Also water feed pipe work under the saddle tank was added to hide the cogs and worm gear. The shape of the cylinders was changed by using some Plasticard sheet to make them look more like the prototype. The buffers were not used on this model, only the supplied coupling plus some lamps and tool boxes.

Paintwork on this model was completed when it was fully assembled, apart from the cab roof which was left loose to allow the cab interior to be finished. To prime the metal and plastic structure I used a matt grey spray primer suitable for metal and plastic surfaces. The finishing paints where oil-based enamels. The green used was a mix of deep Brunswick green and light grey green. The black areas were a mix of matt black on the smoke box and funnel, the other areas being painted in a charcoal grey. I used a signal red on the buffer beams, whilst inside the cab was left in the grey primer finish. Small details such as pipework and safety valves were picked out in a brass metallic finish. The whole model was finished in either a matt varnish or satin clear varnish once details such as the works plates and name plates were fitted.

The set of etched brass plates were supplied by Narrow Planet, who produce a set specifically for “Edward Thomas” from the Talyllyn Railway.

The engine crew was an adapted Dapol Line side work crew figure , with one leg shortened to suit the height of the footplate whilst still looking like a 4 mm scale figure.

Friday, 16 November 2018

009 Tattoo Class 0 4 2

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