Thermoforming a relatively simple process used to convert flat plastic sheet into three dimensional objects. It is used to make a wide range of things from clear packaging for salad and cupcakes, all the way up to hot tubs and truck bed liners.
In it’s simplest form, it involves heating up a plastic sheet until it is pliable and then draping it over a mold and letting it cool so it sets to the mold shape. By adding small holes through the mold and attaching a vacuum pump, the heated plastic can be sucked down over the mold. This is vacuum forming, the most widely used type of thermoforming.
Thermoforming vs. Injection Molding
Injection molding is used to make a wide range of parts but is often not the most cost effective process, especially for lower volume parts.