This will show you a cheap and easy way to make and use a vacuum former.
Step 1: Making the Vacuum Former
We used wood we already had laying around, the only thing we purchased was the "L" joint on the bottom. My husband made a simple box 16" X 16" (2 pieces of plywood 16" X 16" and 2 2x4's 16" long and 2 12" long). Put together with screws to make a closed box. On the bottom he drilled a hole large enough for our vacuum hose to fit into and added a plastic "L" joint we found in the plumbing section of Lowes. This makes it easier for the vacuum hose. It has to fit snug in the vacuum forming table and over your vacuum hose.
On the top you should have a 12 x 12 area. We drilled holes about a 1/2" apart in several rows across the entire top. We added the legs on the bottom, they can be done with anything, just need some room on the bottom for the vacuum hose. And thats it!
My husband painted it, this was a bad idea. Plastic melts, paint melts...not good. Do not paint!!
Step 2: The Frame and Getting Ready to Do Some Vacuum Forming
You need a frame to hold the plastic you will be molding. Most people make 2 frames and sandwich the plastic between the 2. We only made one and used a staple gun to attach the plastic sheet to the wooden frame. Frame inside is 12" x 12" or smaller, the outside doesn't really matter but it needs to fit on the vacuum forming table, not too big. I ordered the plastic acrylic sheets online. You can vacuum form all sorts of plastic though.
Make sure whatever you are copying fits onto your table and within where you drilled your holes. Anything on the outer edges won't be sucked in.
Step 3: Vacuum Forming
Preheat over to around 500 degrees. We used a couple different boards to hold the frame up because the plastic really stretches so give it some room. Make sure your vacuum is ready to go. Once the plastic stretches out, turn on your vaccuum, using pot holders pick up the frame with the plastic and lay it over top of your object. It's hot but you can somewhat help it mold to what you're making. The video is the first one we did, it was hot enough.
The Jason mask is made of sold plaster and is perfect for this.