The problem with it is I had nothing to put this on. The piece of drywall we used to use was damaged a few years back. I wanted to get a 4'x8' board from Home Depot, but it wasn't going to fit into my car. So there are 4 4'x2' boards on top of some planks. But I had nothing to hold the individual planks on. So they're on the floor.
Depending on how thick your 2x4 plywood sheets are, and how skilled you are at woodworking, you could cut a groove into the long edges and join them with splines. Or you could simply build a frame of 1x4’s and screw the plywood sheets to it.
Gosh, I haven’t played with my trains in ages! My most recent efforts were in N gauge.
Evening QT Pi, Hugs
Happy New Year to you and your family.
I remember when my lil bro & dad built a train setup years ago he used an old bed frame.