Wonderflex, that is. it's a type of Thermo-Plast, a plasticized sheet that, once heated, can be shaped and molded to create all sorts of groovy shapes.
I got to use this stuff a lot in prop building and mask making classes back at university, and I love it. We had been discussing alternatives to the plastic milk jugs we've been using for the zombie heads. We wanted better facial contours on the "character" puppets.
So the first pic is of the stuff itself. Comes in a 43" X 55" sheet. (Special thanks to our model JoeJ for holdin' it up for the camera - more on him and the other Zombiteers later)
I have an old plaster life mask that I've been using as a doorstop. Experiment #1 was taking a portion (about 9" X 12"), letting it "loosen up" in a pot of boiling water, then shaping it as it dries. The result is a vague mask. That's okay, we'll be building on it with foam.
**Poobah's Note: I realize the fact that I'm using my own face as the basis for the character design makes me look like an egomaniac. Even though I am, this is really about convenience.
Experiment #2 involved cutting the same size sheet into 3 strips, loosening them each in the boiling water (a little easier with the smaller samples), and shaping them over the life mask. Now I have a jaw, nose/cheeks, and brow to play with.
Now I gotta add foam. I think there's going to be more gluing than sewing this time around. I think it may wind up being a reporter.
If you're interested in getting some Wonderflex of your own, check these guys out - http://www.mainstage.com/Home.asp?ID=2
