Constructing a Broad Gauge 4 plank wagon


As yet no manufacturer produces ready-to-run broad gauge rolling stock, so anyone wishing to build a layout will either have to borrow stock from friends, or they will need to kit build or convert a considerable number of items. This article presents a quick and easy way of producing a decent looking broad gauge wagon using a readily available plastic kit. It should be quite possible to complete one of these in an evening.

This conversion is based on an article by Ian Thomson which originally appeared in Broadsheet No. 5 (Autumn 1981). The original conversion used 2 Coopercraft wagons which is rather wasteful, and butchered EMGS W irons, which is both difficult and unnecessary. For a short wheelbase wagon such as this, compensation is not really necessary. The slop inherent in conventional pinpoint axle bearings should be sufficient to ensure that all wheels stay on the track.

The wagons featured in this conversion were built by the GWR in 1889 & 1890 to lots 408 and 497.

What you will need

1 Coopercraft 1004W kit (make sure you have P4 wheels included rather than the standard 00 gauge)                                    £6.10
2 BGS F040 pinpoint axles (or make you own from 2mm silver steel rod - overall length 35mm)                                                 £0.80
10thou and 40thou plain plasticard
2mm planked plasticard
1mm microstrip
Transfers - either BGS F091 (late wagon - white), or HMRS Sheet 11 (GWR goods vehicle insignia)

Making the Model

Take the ends, and with a fine blade piercing saw, cut each end into three pieces, making the cuts as shown in Fig 1. vertically on the outside of the angle iron stanchions, and horizontally at the top of the bufferbeam.

Modified sides and ends
Fig 1.  Modified sides and ends

New infill pieces should now be made from 40 thou plasticard (cut oversize approx 10mm X 4mm), which should be trimmed to give the ends an overall width of 38mm. Glue these pieces to the centre section, keep flat  and let harden. The offcut end sections need a little packing to compensate for the material removed when they were sawn off. Add a piece of 10thou plasticard to the bottom of each of these and let harden before trimming the excess.the infill pieces for height. Using a scrawker or the point of a small triangular file the plank detail can be extended onto the infill pieces.

Square off the ends of the existing bufferbeam .New bufferbeam end sections need to be made from 40thou plasticard approximately 13mm X 3mm. The ends should be square, not tapered or chamfered. Again trim to match the rest of the end when the glue has set, then  using the scrawker or file emphasise the join between the bufferbeam and the end so as to match the centre section. If not using the kit buffers, you may wish to remove the buffer backing plates at this point.

The sides need the door banging plate (the circular plate in the middle of the top plank) carefully filing off. The wagon floor can be made from a piece of planked plasticard 61mm X 35.5mm. The sides and ends can be assembled upside down on a plate of glass or similar, being careful to keep everything square. For simplicity the floor can be added in the position of the original kit on top of the 'pips' on the ends, but this is not strictly correct and it may be better to file off the pips and add the floor about 1mm up from bottom of the sides.

completed end
Fig 2. Completed end

Both of the solebars need the Dean-Churchward brake lever brackets removing from both ends, and the V hanger in the middle removed. (It's too short and needs to be replaced). The holes in the back of the axleboxes should be drilled out a little to take the brass bearing cups (otherwise the axlebox is liable to split when the bearing cup is inserted). Glue in the bearing cups with superglue, so that the rim butts up to the back of the solebar. The 'lip' on the top of the solebar should be trimmed back till only 1mm remains.

modified solebars
Fig 3. Modified solebars

Glue the solebars to the back of the sides, sandwiching the wheels between them, so that the bottom of the reinforcing strip at the top of the solebar is level with the bottom of the sides. Before the glue sets fully, check that the wheels run level on a plate of glass, and adjust as necessary. Add the brakegear, which should be fitted on one side only, and make a new V hanger from 1mm microstrip. The brake lever, buffers and coupling hook can then be added. Mounting plates for your choice of couplings can now be added, and a little ballast to aid trackholding. I add these to a brass subfloor epoxied into place.

completed wagon
Fig 4. Assembled wagon

completed wagon
Fig 5. Assembled wagon

Painting and markings

The wagon should be painted in a weathered wood colour internally, and externally in red (Humbrol 132 Red Satin). Below the solebar I paint everything black, but there is a school of thought that this also should be red including the wheels. With early film being insensitive to red light, they would look similar.

Markings would have been on the sides, with "G.W.R" on the lowest plank at the left hand end and "To carry 10 Tons" on the plank above. At the right hand end would have the running number on the lowest plank, and the Tare weight on the plank above.  Running numbers would be in the range 11401-11500, 11901-12000, Tare weights would originally have been "5.6.0" when built.

Finished wagon
Fig 6. Finished Wagon

Page updated : 19 Dec 2015