As mentioned, my original intention was to use plywood cross sections. But since the UHMW is available to me, I wondered if it was possible. I really prefer to use the wooden stringers because I already have everything I need.

UHMW (Ultra-High Molecular Weight) Polyethylene. It is similar to HDPE (High Density Polyethylene) but has a stronger chemical bond in its structure.

You can Google UHMW vs HDPE for more info. Most of what comes up is for woodworking stuff but there is some general info there that makes sense.

Chris