The Wandle Valley Railway

This model railway was designed from the start to be portable for showing in local exhibitions. The overal size is about the maximum that can be handled by one person and still meet one of the key criteria, rapid setting up and dismantling times.

The layout was designed for continuous running, but also to get away from the conventional circle. The flattened oval shape was developed to satisfy a desire to present as much of the layout to the viewing public from a single frontal view. It so happens that the protoype site of Mitcham station is situated on a gentle curve, so this was convenient. Because S scale requires somewhat easier curves than 4mm, it was found from sketching out potential plans that a front-to-back dimension of 12ft was about right, with a side-to-side dimension of 16ft. The full scale 'oval' was sketched out on the floor of the garage attached to the house. This gave a feeling for how the layout would look, right from the beginning.

Baseboard Sizes

As the overall layout would have no straight front or back edges to each board, the opportunity was taken to make the front centre 3 feet wide, tapering to 2 feet wide at each side and 18 inches at the back for the fiddle yard. The ends of each board are set out 90 degrees to the track ends for the mainline, and as a result the board ends seem to radiate out from a virtual centre point like the spokes of a wheel.

The diagram shows this. A feature of this overall design is that no board has a completely straight edge, but boards on one end of the oval are mirror images of those at the other ends. The primary benefit of this feature is that 8 of the 10 boards are 'boxed' up in pairs for transportation purposes.

Based on experience with previous layouts, it was decided the boards should have a maximum corner-to-corner dimension no greater than 4ft 6in. Given the very light construction techniques used, this gave the maximum board size (board no. 6 on diagram) of approximately 4ft 6in. by 3ft. Although this is the centrepiece, which carries the main station and platforms, there is no complicated trackwork on it, only the 'up' and 'down' tracks. As a matter of interest, 'up' is the eastbound track (to West Croydon) and 'down' is the westbound track (to Wimbledon).

Baseboard Structure

In 1983, when planning to build a previous layout in EM gauge, a fellow modeller and I developed a method of using 1/2 inch thick softboard, reinforced and supported by very thin plywoodstrips, glued to form a honeycomb structure, but with somewhat deeper sideframe members.

The accompanying sketch shows the basic principle. The plywood is 4mm thick, known here in Canada as 'doorskin'. Originally, we made the strip depth 2 1/2 inches. We tested a 4ft long board under the weight of one of us and the deflection was barely measurable. The boards for that layout lasted for 9 years in constant exhibition use, and 2 of them have been incorporated into my permanent EM layout at home. After 15 years there has been no deterioration.

Subsequent to using the 1/2 inch softboard, we experimented with using 1 inch think dense styrafoam, formed in flat, molded sheets, know here as 'Styrafoam SM'. This is used extensively in the building industry for wall insulation. It is fairly rigid and being styrafoam is impervious to normal heat, cold and moisture. It seemed perfect for our needs for a rigid baseboard top. By reducing the plywood strips to 1 5/8 inch depth, it has been able to form a very light, but rigid baseboard that extremely easy to carry; an issue of considerable importance as one gets older! It was decided that the WVR baseboards should be constructed this way.

Photo no. 1 shows the honeycomb structure, which is set in 6 inch squares.

In addition, each board would have attached permanently its own fold-up pair of legs. The initial intention was to have Board no.6 to have 2 pairs of fold-up legs, at each end, but it soon became clear that stowage of both pairs into the recess under each board would be near impossible, so Board no. 6 has 1 pair of fold-up legs, as all others (except boards no. 2 and 10), together with a pair of removable legs at the other end.

Photo no 2 shows this, with the fold-up legs folded back and recessed against the baseboard structure.

The legs are also constructed of 4mm plywood, fabricated as hollow rectangular tubes, with spacers. These are very light, but immensely strong. The construction materials used for them consisted of only 4mm plywood strips, some small spacers, white glue (PVC), and about a dozen small pins used to hold the wood structure in place while the glue set.

In order to gain extra height, which could not be accommodated in the baseboard recess, plywood extenders, 9 inches long, were constructed for each leg. These are removable, but a tight fit. Each of these has a 6 inch bolt screwed into the base, with an eyelet top, for ease of adjustment of baseboard height on uneven exhibition floors.

Board no. 1 is similar to board no. 6 in having 1 pair of fixed fold-up legs, and 1 pair of removable legs. This means that Boards no. 2 and no.10, do not have legs, and act as 'bridge' boards only. This simplifies setting up and dismantling at exhibitions.

Miscellaneous Baseboard Items

Boards are joined by standard 1/4 inch coach bolts, all of a standard length, but loose fitted in the baseboard holes at each end. In addition, each pair of baseboard ends have 2 EM Gauge Society baseboard joiners, one male and female on adjoining boards, which give perfect board alignment. In addition Board no. 6, being the largest board and always the first set-up, has a narrow ledge added at each end for the adjoining boards to rest on. This assists set-up, primarily enabling the complete set-up to be handled by one person, if necessary.

Wiring is by no. 20 swg solid copper wire, colour coded, for most of the layout, although some multi-strand wire is used. Inter-baseboard connection is by 9-pin or 25-pin computer plugs and sockets, the socket being permanently attached to each board, with the plug on a flexible lead. This folds back into the recess of each board, behind the fold-up leg, for transportation. The primary principle behind this construction method is to enable very rapid set up to take place at exhibitions.

Set Up at Exhibitions

One of the criteria laid down was to be able to set up in 1 hour at an exhibition, by just one person. Every aspect of the design has been determined with this in mind. As I have been the sole builder of the layout, and understand every aspect of it, I have found set-up achievable in about 45 minutes from the time all the boards are put on the exhibition floor, to running the first train. With knowledgeable helpers, which I was fortunate to have at GBTS '98 (Brampton, Ontario), the net set-up time was about 30 minutes. The most difficult and strenuous activity at exhibitions has turned out to be the unloading and loading of my trailer.

Return to Scenes on the Wandle Valley Railway

Version 1.1 August 1998