Having test built and painted a couple of locos from the kit
I’ve come to realise that the choice of assembly sequence is best determined by
the paint scheme one wishes to adopt. The real imperatives lie in the
preparation of the castings. All parts will have flash, an inevitable
consequence of my low tech, home casting approach, but it is easily trimmed
back with a sharp craft knife and abrasive papers.
Kato Chassis Modifications
The alterations to the chassis are limited to reducing the
length at each end by 4mm. Prising away the n gauge couplers then cutting square across the chassis on the
mid point of the coupler pocket is an easy way of achieving this reduction.
Footplate and Buffer Beam Casting.
Trim away flash from the edges of the footplate and the
remains of the runners from the top surface. Turn the casting upside down, on
the bottom of the footplate the area to be cut away becomes apparent as the
thinner area in the middle. Follow the edges of the thinner section with a
sharp knife, the resin cuts easily.
There will be some pitting pf the top of the footplate
caused by air bubbles becoming trapped in the mould. It has proved impossible
to get a cast of this section without this happening; however these blemishes
fill easily (I recommend Squadron Green Putty or a paste mixed from superglue
and talc) and sand level easily on a large sheet of fine wet and dry abrasive
paper. This will be the only casting with this pitting on a visible surface.
Test fit the shortened Kato chassis; trim back if necessary
to a snug but resistance free fit.
Cab Casting
The greatest preparation work lies with the cab. Once all
the required openings are pierced it can seem a little delicate, following the
suggested order of work maintains strength for as long as possible. The single
cab front and both cab rear windows are opened out first. With a sewing needle
in a pin vice gently scribe round the inside of each window in turn using the
inside of the frame as a guide. Gradually deepen the cut until a white line
appears on the rear when the cab is held up to the light. This indicates that
the resin is almost cut right through and the centre of the window can be
pushed trough with a suitable blunt instrument.
The same technique is used for
the lower cab front cut away to clear the chassis. Leave intact the lower
sacrificial lip to the cab for the moment as it adds strength while the cuts are being made.
The
last openings to be cut away are those on the cab sides, again try to
preserve the lower lip. Once all cab openings have been cut out, the
lower lip
can be gently pared away and trimmed back to the base of the cab proper.
If in doubt about where to trim back to check with the photo on the
home page.
The hardest part is now behind us.
Bonnet Casting
The bonnet can have its lower lip trimmed back straight
away, no strength issues here, followed by cutting away the thin area at the
rear to leave room for the chassis. The dimples on the top of the bonnet at its
rear edge locate the holes which require drilling for exhaust and fuel tank. I
find that a 1.4mm drill is the best match for the spigots when the castings are
cleaned up.
Sideframes and Buffer/Couplers.
Both just require simple cleaning of the flash and checking
for fit on the footplate casting.
Fuel Tank and Exhaust
I find that paring away of the flash with a
sharp knife is the best way of cleaning up the castings. The exhaust requires
cutting to a suitable length top and bottom of the silencer section. The Fuel
tank needs one of the spigots cutting short (about 1mm proud of the tank) to
represent the filler cap and the other left long to seat into the fixing hole
drilled in the bonnet top.
Painting and Assembly
As I mentioned earlier the assembly stages are best determined by the required paint finishes. I can recommend Halfords or any other reputable brand of acrylic auto primer as a base coat. I use talcum powder as a release agent and have not found it necessary to indulge in any cleaning ritual of the resin casts before spraying. Finish painting of the components will ease getting a sharp delineation between differing colours. It is advisable to paint bonnet and cab both inside and out as access once assembled is awkward.
Superglue has been my adhesive of choice, as it leaves little time for adjustment a dry run to check the fit of parts is a very good idea. Slight trimming of sideframes and couplers may be necessary to get then to fit snugly into their recesses. Once the footplate, sideframes and couplers are assembled, pop the cut down Kato chassis into position. The bonnet is a snug fit over it and this will help centralise it on the footplate. Use the cab to work out a position for the bonnet where there is equal space between radiator to footplate front and cab back to footplate rear, and glue the bonnet into position. When set glue the cab to the footplate and bonnet back. Finally fix the exhause and fuel tank into position, the greater overhang of the tank towards the centre of the loco.
Painting and Assembly
As I mentioned earlier the assembly stages are best determined by the required paint finishes. I can recommend Halfords or any other reputable brand of acrylic auto primer as a base coat. I use talcum powder as a release agent and have not found it necessary to indulge in any cleaning ritual of the resin casts before spraying. Finish painting of the components will ease getting a sharp delineation between differing colours. It is advisable to paint bonnet and cab both inside and out as access once assembled is awkward.
Superglue has been my adhesive of choice, as it leaves little time for adjustment a dry run to check the fit of parts is a very good idea. Slight trimming of sideframes and couplers may be necessary to get then to fit snugly into their recesses. Once the footplate, sideframes and couplers are assembled, pop the cut down Kato chassis into position. The bonnet is a snug fit over it and this will help centralise it on the footplate. Use the cab to work out a position for the bonnet where there is equal space between radiator to footplate front and cab back to footplate rear, and glue the bonnet into position. When set glue the cab to the footplate and bonnet back. Finally fix the exhause and fuel tank into position, the greater overhang of the tank towards the centre of the loco.
Hopefully the Kato mechanism will be an easy friction fit in the body. If it proves to be loose a small dab of Uhu provides the easiest method of fixing it in place. It's bond is easily broken should it be necessary to extract the chassis.
