Having chosen a modular standard, the first thing you need to do is start cutting…
No not really, the first thing to do is read the standards document because this will usually give you very strict guidelines on the dimensions of the endplate. The endplate is where different modules will be connected together and for this to happen easily and reliably, the endplate needs to be uniform on all modules of the same standard. As it’s such a key part of the module, it makes sense to design the rest of the framework around the endplate.
Whichever standard you use, the endplate itself will likely have a set width and height and the position of any cut-outs and holes (for wires/bolts) will be standardised.
The location of the track or track centres will also have to be standardised to the centre of the endplate or some distance from the front or rear of the endplate.
Having never built a module I thought it best to have a go at building a couple of modules with the simplest rectangular endplate. I’ll cut the endplates as shown in the FremoN-RE endplate specifications and then build the framework shown below to support the track and scenery.
The endplate and framework will be 100mm high and both will be cut from a sheet of 12mm thick plywood. Anything inside this ‘outer’ frame will be made from cheaper 9mm plywood. The ‘inner’ cross-members will be 82mm high to allow 9mm-thick plywood to be fixed to the top and bottom edges and still stay within the confines of the 100mm high ‘outer’ framework.
The piece of 9mm plywood running the length of the module that forms an upper-surface (the darkest piece in the diagram above) will support the trackbed and the piece of plywood running the length of module on the underside will help prevent the module racking/flexing.
Where two pieces of framework touch, 20mm x 20mm square-section, plained wood will be glued and screwed in place to help keep joints square and add a bit more strength to the framework.
Screws will be driven into pilot holes made on the plywood side. It’s not the easiest thing to illustrate on an axonometric grid but here is a diagram anyway.
The modules can be made longer simply by extending the ‘outer’ frame and adding more cross-members at regular intervals. Typically you’d add a cross-member every 30cm but it’s recommended to keep modules under 120cm to ensure they’re easy to handle and transport, so I’ll need to change the spacing a little on the longest modules as shown below.
All of this means my standard module will be 105cm wide, 40cm deep with a 10cm high framework.
Now, it’s time to start cutting…