Process: A preformed sheet of material is placed in a mould then warmed and sucked or pushed into shape using a vacuum. Neither high heat nor pressure is required so moulds can be made from cheap materials such as MDF or cast aluminium.
Introduced: 1890 for use with cellulose nitrate.
Plastics: Most sheet thermoplastic materials, for example cellulose nitrate, cellulose acetate, polystyrene, polypropylene, polyvinyl chloride, acrylonitrile butadiene styrene, and polycarbonate.
Marks: None.
Tooling cost: Low.
Production volume: Suitable for low quantities or even one offs, but can be mechanised to speed up the process.
Uses: Shallow forms: baths and boat hulls, bowls, margarine and yogurt pots.