This shop built vacuum former holds a 15" x 30" sheet of  .060 Pet-G Vivak, we used to form a 6" x 11" tray, 1" deep on one end of a textured panel. The pattern  is made from particle  board for the texture we needed to diffuse light.

To move the pattern and thermoforming plastic closer and away from the heat we used an old drill. The high vacuum pump is also shown in the photo.  It's also used on a vacuum table used to debubble investment for lost wax casting.

We formed a tray from sheet aluminum and covered it with high temp sheeting from a fireplace store. The heaters are two 2500 watt calrod elements from an appliance repair place. Cost about $50. It's plugged in to our 60 amp welder receptacle.

The heater is moved over the forming area with drawer slides. To form the plastic, the mold frame is raised to the about 6" from the heat elements. When the plastic drapes, vacuum is applied.

When the plastic forms completely around the pattern, the heating chamber is pushed away as shown in the photo. The squirrel cage fan helps cool the finished plastic. This design allows us to leave the heating elements on and get about 4 minute cycle times. 

Front view. Many of my projects are made from scrapped parts and materials that we have. It cost less than $100 and a couple days to build.