If any one is building the 4x8 layout that CTT started in December, I would like to ask about the difference between using 1/4" ply vs. 1/2" ply. The 1/2" seams to be a better choice for putting screws into, but also makes the bench work a lot heavier.
Also what length screws are you using to lock down the track?
I am not building the layout, but have been following the progress. From a building point of view, the 1/4 will provide adequate backing for the foam and maintaining the frame square without the weight. Since it is relativly small and you will be able to reach all points of the layout, there would be no need to climb onto the layout or build it to support anything in excess of more than a few pounds per square foot. As far as holding screws the 1/2 would hold a screw with more gusto, but the 1/4 will hold enough for the purpose intended. Like all construction, there is always trade offs of cost, strength, weight, and what is needed and you balance them as you see fit.
Jim
I just recently finished my new layout which measures 8’6" x 13’10" in a “C” shape. It has 2 loops on the upper level and 1 on the lower level. The table is constructed with 1x4s and the table top is 1/2 inch plywood. I used 3/4 inch flat head screws to attach the track. Do not over tighten!
Cobrabob.