Please tell me more. Do you mean that jigsaw cut plywood like in the photo above is prone to warping? Or is it a lack of full sheet covering the frame?The hard part about this is; after you have your track laid and start your scenery then after a warm humid day you come to your train room and find your road bed looks like a roller coaster.
You have no doubt seen plywood that has been left outside, exposed to the weather. It's terribly warped. If your house is climate stable you may not end up with warped plywood. On the other hand, even with sealing it, it can still end up warping then ya have to do the fixes. A lot of times just putting 2x4 under the warped part and using screws to secure it will smooth out those HO scale hills. If takes a little bit of ingenuity to figure out but its not impossible.Please tell me more. Do you mean that jigsaw cut plywood like in the photo above is prone to warping? Or is it a lack of full sheet covering the frame?
Yes and yes.Is the issue the narrowness of the plywood strips, or is it that the attachment points are too far apart? A combination of the two?