plastic sheeting attempt 3

Still a way to go, but it's a lot better than my previous attempts at the plastic sheeting. It even looks a bit like art glass with light behind it.

It came out of the press totally flat, warping while it cooled. Also the surface isn't what I want for utility purposes, so I'm wondering whether I could roll it, or if I could get a big metal sheet to keep it flat against the cement floor while it cools. Or both, of course!