The success or otherwise of this
kit depends on the care and diligence brought to bear when preparing the
castings. They will require opening out, trimming flash and filling but providing a careful and unhurried
approach is taken a good result can be achieved by those with average
skills and experience.
Before starting on the specifics there are a couple of general points worth making. Because the castings are home produced, without any fancy equipment tiny raised bobbles occur from time to time, some may be seen in these illustrations. In most cases they break away easily by thumbnail, stubborn ones give way to a jewellers or terminal screwdriver. I use superglue (generic pound shop brand) to stick the castings together. If I need to fill any areas I mix up a paste from talcum powder and superglue. Though I've shown the assembly process with unpainted castings it will pay to paint some of the components before assembly. The interior of the cab, and that section of the bonnet which is inside it will be extremely difficult to paint if tackled after assembly.
To begin, take the footplate/frame unit and trim away the sacrificial support structure and open out the thin area in the centre of the footplate until it is a snug fit over the Tomytec mechanism. Open out the cab footsteps. The raw casting is pictured on the right, the finished casting to the left.
The Tomytec mechanism also requires work. The simple hook and loop couplings at either end require cutting off; I snipped them away with a pair of electrian's sidecutters. The upstands at either side of the chassis centre tray need to be trimmed so that they are flush with the top of the footplate casting. I marked where they needed trimming back to by placing the footplate casting over the mechanism and scribing the upstand using the top surface of the footplate as a guide. The Tomytec plastic is quite soft and cuts away with multiple passes with a sharp craft knife.
The Tomytech mechanism comes with a pair of side frame blanks which plug in to the three holes in the block between the wheels; push these into place. Take the sideframe castings, trim away any flash round the edges and remove any trace of the feed sprues on the rear by sanding flat. I place emery cloth on a flat surface and rub the rear of the casting on it. Glue the casting to the Tomytec sideframe blanks; the axlebox mouldings are off set on the resin castings which should be orientated so that they are in the lower rather than higher position.
The mechanism complete with sideframe castings is now inserted into the footplate unit.
Next trim away the excess support on the bonnet casting. Drill a 2mm hole for the exhaust centred on the dimple cast into the upper front of the bonnet.
Fix couplers to the footplate unit front and rear. The cast recess should locate for height and centre.
Prepare the cab casting by opening out the cab front and rear spectacles. Next open out the doorways followed by the cut out to fit round the bonnet. Finally cut away the support structure. Following this sequence maximises the rigidity of the cab at each stage of trimming and opening out.
Fix the radiator casting to the rear of the bonnet as shown. The full size Kerr Stuarts had the radiator set off centre as shown and with the radiator header above the level of the bonnet.
Fix the bonnet to the footplate. Though he mechanism locates the bonnet laterally I found it helpful to slide the cab into position to hold the rear of the bonnet in place while I glued the front section in place.
Fix the cab into position. For both this and the bonnet I found it useful to tack the castings into place, check and then when set run a full bead of glue into place.
Trim back the exhaust casting as shown, more will be thrown away than kept but this is a function of the casting process.
The casting is fixed into position on the bonnet top, the 2mm hole previously drilled may require opening out a touch, but better too tight initially than too loose.
Each kit contains a pair of small rectangular castings (not pictured) representing oil or fuel cans ('flimsies', the precursor to the 'Jerry-can') which may be used to detail the loco, its shed or workshop.
