Coach building in Plastikard with Geoff Kent - 1st June 2022.

This was a return visit from Geoff who came to talk to us before lockdown about using Plastikard for Buildings. He reminded us that he did write a series of articles
on coach building in the MRJ, editions 222, 226 and 228 which he thought were still available as back copies from Wild Swan/Cygnet/British Railway Books.

Geoff uses a variety of thicknesses of sheet from 5 thou (0.005”) to 60 thou (0.060”). His modelling is in 4mm to the foot scale and he uses 10 thou for steel bodied stock and 15 or 20 thou for wooden; the former if bolections are to be added. He marks out both sides on the plastikard, one the correct way up, the other, upside down above it. This helps line up doors and windows etc where the coach is symmetrical. There is no need to leave a gap unless the windows are very near the top of the coach. He uses a single bladed safety razor blade rather than a scalpel. As the sheet can stretch when cut, he leaves it as part of a whole sheet while cutting out the windows; then cuts out the side to size. It is most important to keep the top and bottom of the windows in line as this really shows up if wrong; the widths are less obvious.

He uses scraper cutters for scribing and cleaning up edges. Windows with rounded corner are cut out with a 45 degree straight corner which is then filed to the required radius. Once the side is cut out, it is time to form the ‘tumblehome’ or ‘turn under’, if appropriate. The lower part of the coach side is rested on the edge of a piece of card and a round-ended embossing tool is run along the back of the coach side repeatedly until the required curve is achieved. This is repeated on a second piece of plastikard which is laminated onto the back of the coach side using plenty of solvent and avoiding any air gaps. This ensures it will not move. Some of his coaches date back to the 1970s and are still keeping their shape. Panelling is made by cutting out a lattice of 10 thou plastikard. This is done in short sections up to 2” long. It is ideal if the joins are at doors but joins can disappear very easily with plastikard and paint. If necessary, he uses flat jawed pliers to hold the plastic while filing it to size. Many pre-Grouping coaches had bolections (mouldings that overlap panels). If these have sharp corners, they can be made from strips of plastikard. If rounded, they need cutting from one piece of 10 thou. It may be easier to make these oversize and trim to size or glue to the coach sides, then file to size. Geoff pointed out that plastikard is easy to repair; you can even make filler from filings and solvent. Droplights can have a few left open to improve the realism of the model and to ensure the coach body is not sealed which can cause problems with trapped solvent. Outside details can be made from plastikard strip and rod. Hinges are rod glued into the door scribed groove. Grab handles are bent up from 32swg wire. Door handles filed from brass pins, vents over doors are best scribed if there were louvres.

For glazing, use either Slaters Plastiglaze or Evergreen clear. These can be glued in with solvent but don’t get any on the glass itself. If spray painting, paint before the glazing; hand painting can be done afterwards. Any sliding vents can be added to the glazing using DL Limonene, not Mek Pak (if you can get it). Obscured glass may be painted white inside or sanded inside depending on the prototype. If it was engraved, you can try scribing the pattern on the inside with a needle in a pin chuck! Brake end security grilles are etched on the inside of the glazing. If necessary, you can run paint into these grooves. Corridor handrails are nickel silver wire glued behind the windows. No Smoking signs can utilize transfers or you can paint them with a mapping pen (used in calligraphy). Curtains are also main from plastikard, they must not touch the inside of the glazing. Duckets can be built up on the coach side. They consist of three parts: two sides and a cover. The windows can be painted black or charcoal grey from behind as you are unlikely to be able to see inside.

Coach ends can be simple and flat, sometimes with planks scribed in. Geoff fits the ends inside the sides. It is important to allow for the roof when fitting the ends. If the ends are bowed, the central section can be built up with 40 thou plastikard with an overlay curved to the required profile. If there are windows in the ends, they can be painted unless you are modelling a GW railmotor which has large windows and needs a cab modelling! The fittings on the ends can be modelled with plastikard, wire etc. Steps are made from 10 thou stuck on perpendicular to the ends and the flange added with a narrow strip underneath for extra support.

Geoff makes gangways from cartridge paper folded as a concertina with 2mm wide strips. They have a metal ‘hoop’ at the outer end to hold their shape. They are painted with thinned down enamel. They will need sprung buffers but cannot really have screw couplings between coaches, only at the ends of the rake. He uses bar couplings under corridor connections.

For assembling the coaches, glue one end to a side and the other end to the other side. This ensures a right angle. Fit the 40 thou floor at the same time as joining the two L-shaped halves. Wooden solebars are made from 60 thou. Steel has a thick vertical of 30 to 60 thou with just the lower, visible flange in 10 thou. Coach footboards are made from 20 thou and bogie footboards from metal. Interiors consist of the corridors, seats and compartments modelled in one, drop in unit. They should not touch the inside of the coach sides. If you cannot see it, don’t model it! The interiors can be painted Humbrol SR wagon brown for varnished wood. Upholstery can be painted an approximation of the original colour as it wont really be seen.

The roof starts as a three layer sandwich, each 30 or 40 thou. The first fits between the sides, second forms the gutters and the third has a rebate for the roof edges. Profile pieces are added about every 2”. Measure the circumference of the profile with baking foil and cut a roof piece of that width, 1mm longer than the coach. Shape it using the same method as the ‘turn under’. For a simple, single arc, use 20 thou, for a more modern three arc roof, use 10 thou. Laminate two pieces to retain the shape. Stick one edge to one side. Leave it to go off then pull it down and glue the other edge. Do not glue it to the profiles, only the ends. Any ripples in the 10 thou will disappear when the second sheet is added. Domed roof ends are built up and carved from thicker plastikard. For clerestory roofs, make the roof as described and add the clerestory afterwards. Geoff glues roofs on; they are not removable. Underframe details can be sketchy. Truss rods are wire if round or square section if made of angle as it does not really show. Battery boxes are made up from 20 thou. Other details included as long as they show! They can either be made up or bought in castings.

Words: Nick Coppin
Photos: Sam Ryan
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