2" extruded foamboard on its own would also be plenty strong on risers with 12" spacing. We use it with 24" spacing for our modules at <!-- m --><a class="postlink" href="http://www.hotrak.ca">http://www.hotrak.ca</a><!-- m --> and it is very easy to work with. Lightweight is important when you are assembling and dismantling a ~50'x~25' layout every six weeks.


Andrew

videobruce Wrote:or that 'stuff' I hate; flakeboard/OSB (at a much cheaper cost).

The thing is, not only is it much cheaper, but it typically stays flat unlike plywood.

Mark

But, doesn't that make turnout control that much harder going through that additional thickness??