Vacuum forming (thermoforming)

A plastic sheet is heated until soft, draped over a mold and pulled tight by vacuum (or pressed with air pressure in pressure forming, which captures more detail). After cooling, the part is trimmed. Molds can be wood, resin or aluminum, so tooling is far cheaper and faster than for injection molding.

It suits large parts with fairly simple, open shapes at modest volumes: equipment covers, kiosk and machine housings, trays, packaging and panels.

Where it bites: only one side of the part is precisely controlled, the wall thins where the sheet stretches most (corners and deep draws), bosses and fine features need secondary operations, and trimming adds cost and variation.