For .030 or .040 polypropylene, go to www.mcmaster.com, on the home page in the bottom right corner,under raw materials and springs, click on plastics > film > polypropylene > thickness. A 12" x 12" X .030 thick piece is $5.64. I also use Garolite grade 10, for the mounting pads on my blades, you can check out the specifications for it on this website also. I also buy my 4/40 socket head capscrews here to by boxes of 100. Usually get my order in about two days. The only problem I have with this web site, is that I usually end up buying more than I had planed on. Also, if you send me your e mail address, I can send you pictures of a rotor head that just might work on your gyro.