Vacuum forming plastic

I wanted a round 50s style canopy for my robot, and since I have been thinking of vacuum forming plastics for a long time, I decided to give it a try! First I had to construct a Vacuum forming machine, in this case it's just a box with alot of small holes on top and big hole in the side for the vacuum cleaner (to provide the vaccum). I used Super Sculpey to shape the plug for the canopy. 

I used a sheet of 0.5mm Petg plastic and used a staple gun to fix it to a frame. I heated the plastic sheet in the oven at 140º C for about 1.20 min. I pushed the heated plastic ontop of my plug on the vacuum machine and the then vacuum pulls the plastic tight against the plug and when the plastic cools it's finished! Sounds simple, but it took a few tries before got the plastic in exactly the right temperature and I was very surprised when it finally worked.