Vacuum forming is a common method of forming plastic sheet into a bespoke design. Firstly, a tool is constructed, which resembles the required product design, with tiny holes drilled into the tool to allow air flow. This is inserted into the vacuum forming machine. A plastic sheet is then heated until soft, before being laid over the tool. When a vacuum is applied, the heated material is sucked onto the surface of the tool and clings to it, adopting its shape. The material is then cooled and allowed to harden, before being expelled from the mould.
Vacuum forming can be used to manufacture products from an array of plastics including ABS, polypropylene, polycarbonate, PVC and acrylic. It is also a relatively fast process, with lower tooling costs than most other moulding techniques, which makes it a great option for producing plastic parts with thin walls. However, as only one component can be formed at a time, vacuum forming is best suited to lower batch runs - in addition, secondary processes may also be required to improve quality and finish.
