From take-out coffee lids to airplane interior panels, vacuum-formed plastic is everywhere. And for good reason: vacuum forming makes light, durable, and cool-looking 3D parts. Here's how to cook some up in your kitchen.

Bob Knetzger's favorite childhood toy was the Mattel Vac-U-Form. He recalls the way the flat plastic changed shape by invisible vacuum power was magical and fun to watch! Today, Knetzger uses vacuum forming to make toy prototypes in his own shop. While he usually uses a professionally made vacuum former, in a pinch, he's used this ultra-cheap, homebrew rig with great results.

Large, commercial machines have built-in vacuum pumps, adjustable plastic-holding frames, overhead radiant heaters, and pneumatic platens. The Guerrilla Vacuum Former is much simpler. It uses your oven to melt the plastic, and a household vacuum cleaner to supply the suction. All you have to build is a simple wooden frame and a hollow box. Knetzger shows you how to do it, then use the device to create a tiki mask that also makes a great Jell-O mold.

This project first appeared in Make: Technology on Your Time Volume 11.