I have enjoyed reading the entries in this forum and thought it time that I jump in and let fly. I look forward to feedback from those that have used the foamboard in the following regard. I have seen many examples of the pink or blue foamboard used but they seem to be on level surfaces, often modular layout sections. How well does it work for multi-elevated railways? It would seem that many more risers would be required for uniform support? I can understand how the soft foam for roadbed would work well on the foamboard but again I need to be convinced that for elevated track the foam board in narrower strips offers enough rigidity without increasing the number of risers to the point of not being time or cost effective. An additional concern of mine is the mounting of switch machines and other under the sub roadbed electrical devices and hardware.
My multi-level (virtually none actually level) track plan is being executed using a sandwich approach. The bottom slice is thin plywood. The filler is 1/2 inch foam. The ballast former (usually cork or WS foam rubber) is 1/4 inch foam (aka fan-fold underlayment) cut to appropriate shape and contour. The whole is glued up using latex caulk for adhesive.
In a few places with extremely long spans, I’ve tucked the sandwich inside a steel stud. The longest such span is about eight feet. I don’t hesitate to brace shorter spans by screwing angle iron to the plywood bottom layer.
2-inch pink foam works pretty well for inclines. I just cut a narrow strip, and mount it on T-risers. In this picture, the risers are mounted on the cross-pieces, which are 16 inches apart. The foam is stiff enough to span this distance, and probably more, without any problems. Here’s an under-table view. The incline here is the narrow strip running from the upper left to the bottom, where it’s close to merging with the upper level.
I hadn’t considered the thicker foam. It does however present a concern if one line is crossing under another as far as vertical clearance. Great photo and explanation.
You could also use Woodland Scenics foam incline and riser sets. They may be the easiest way to maintain a constant grade. I will be using them on my N scale layout. Here are some links to the product.
Or, I know there are a few people on this forum that make their own inclines and risers out of foam board. I’m sure they could explain how if you are interested.
