One of the themes that guide the educational strategies at our middle school is “design thinking.” Bringing something from an idea into an action or an artifact is usually an iterative process – try something, see what happens and learn from your observations, then either make adjustments or try again. It sounds pretty obvious (especially to active model railroaders!), but some folks develop a lot of anxiety because they feel that they need to get it right on the first try (maybe you can relate to that). So we try to encourage kids to include the expectation of reworking things into their concept for a task.

Designing a design is no different. My plan for the layout started as a simple extension to the Inglenook but as I began to take more and more of the opportunities that my room created into account, I discovered that I had a couple of druthers that began to drive the overall scheme. One was the desire to operate a town on a siding. In addition to meets and passes, the flexibility to keep switching while another train barrels through on the main appeals to me. So, rather than treat the lead on the Inglenook as the main, I thought of it as a siding.

I didn’t want a straight main line along that blackboard wall, however. There is just too much good math happening in curves (including vertical curves, so I wanted to have some grades and changes of grade). As I played with how to take off from the Inglenook tangent lead to connect with a curved main I realized how much more latitude I would gain if that lead wasn’t straight. I would need to relay that strip of track so that it ran off the board near the corners, or even on the long side.

Then it finally hit me: don’t build onto the actual Inglenook module, build exactly what I want from scratch! That decision lifted my thinking a lot – not only did it make the design more flexible overall it simplified the benchwork challenges considerably. And best of all, I could keep the Inglenook as a separate puzzle game layout! No interruption in operations for construction!

I suspect you might find my approach to benchwork controversial, but it seems to be working out pretty well considering my “given” of having it built by very inexperienced hands. Rather than using beautiful clear straight lumber and worrying about dead level benchwork I decided it was an appropriate economy to use readily available, inexpensive 1x2 pine stock sold in bundles at Home Depot, with virtually none of them even close to being straight. I built my last layout with gorgeous, precise “filet of pine” and would have preferred to use it again to promote careful work, but with a layout along a wall I didn’t really need the benchwork to provide a reference level line. Many of the pieces are somewhat ridiculous, but selecting usable pieces would be something the students should learn how to do. And, having to account for some warping and irregularity means they can’t take anything for granted.

I needed to decide on a layout height. I wanted it close to eye level for the kids, but needed to maximize the amount of that blackboard that I could use, which meant it would have to be a little bit lower than ideal for most of the kids, between 38” and 42” was about the best range. Getting at that blackboard (mostly by my own arms, not so much by the kids) also meant the width needed to be limited. I decided 16” would be about right, with bumps and squeezes where needed.

Although these dimensions really said “shelf layout” to me I knew I couldn’t attach anything structural to those blackboards, so I was going to need legs to the floor. Since it was going to need to be dismantled every summer, bolt-together modules made sense.

Modules this narrow wouldn’t need four legs of support if I could anchor things to the wall below the wooden chalk tray along the base of the blackboard. I played around with designs for this but then realized that could be a problem when I took the layout apart and the modules weren’t freestanding.

The first module doesn't need legs as it can sit on top of a bookshelf.

When playing around with arrangements of things in three dimensions, like benchwork details, I often find it helpful to use isometric grid graph paper. It makes it very easy to work out how things will fit together, and I can produce sketches that make my ideas clear to others. The kids learn a lot about spatial coordinates when they use it. 

Fooling around with many different arrangements led me to settle on a design approximately like the sketch below. Each module would be eight feet long, L girders supporting 1x2 open frames and spanning 2x2 legs. 1/8” masonite gussets rather than cross braces. I wasn’t sure if the gussets would perform well until we actually got one of the modules built and clipped to the wall. Truss head screws attach the masonite to the wood. 

Time will tell if the lightweight, portable assemblies are a sufficiently robust design, they look pretty spindly, but once they're attached to the wall (and each other), they are quite solid.

Jeff