The portable 5x8 standard gauge layout I have been taking to shows is quite heavy. It was made from stuff on hand, so cheap. A few in the club have been discussing a way to do lightweight, expandable modules. We have opted for 31.5" squares of 3/16" marine type plywood with 1x2 select finished pine for sides and a cross support. 4 of these panels weight about the same as one of my old panels. With 2 panels wide, we have a 57" outer loop and a 42" inner loop. The outer loop will be 5 rail, running O is always possible, but none of that plastic stuff allowed. The length is only hindered by how many panels we have to run. There will be no legs, just folding tables to set up on. Right now there are 5 of us committed to the project, two of us are well along the way. The two of us will set up and run and work any bugs out before making the panels for the others. We have really tried to keep it as simple as possible.
We will have plexi guards on the outer edges and have clearance for a 400E.
Steve