SpudFiles

I've been looking for a place that sells Sheets of PVC. I saw that Joel from SPUD TECH used it on his Mega Launcher. I don't want to use wood i think it looks cheesy and I can't seem to find it anywhere.

mcmaster.com

Call plastics stores near you, they usually have it, or you can go to McMaster, OR you can make your own.

What exactly are you using it for? How much do you need?
For pistons/valve, you can use acrylic as well. Just call or go to Lowe's or Home Depot and ask if they can get you a few samples of a solid surface countertop to take home and see it in your own light. ...or have your parents do it. You can cut it to fit your own needs (pistons) and it holds up great. Just make sure you get Corian or Hi-Macs, as these are 100% acrylic and not a poly/acrylic blend, which is more brittle. Often times they have a 3"x4" scrap/sample their fabricator has brought them or a 6"x6" sample from their distributor. If this fails at the store level, call us the fabricators themselves. I'm sure they wouldn't mind parting with a few of their scrap pieces. This stuff is 13mm thick.
You could use it as manifolds as well... explain to the fabricator what you are doing. We can weld it by using an acrylic 2-part epoxy You can then take it home and drill out whatever you need to. The material is pretty strong stuff and the welds hold 80+% of the materials strength.

I'm using it as stand for a duel combustion cannon. I need two sheets half inch thich 12x24.

i saw some at walmart the other day day there were small though