What is Vacuum Forming
Vacuum forming is a simplified version of thermoforming, whereby a sheet of plastic is heated to a forming temperature, stretched onto a single-surface mould, and forced against the mould by a vacuum is formed into permanent objects such as turnpike signs and protective covers. Normally draft angles are present in the design of the mould (a recommended minimum of 3°) to ease removal of the formed plastic part from the mould.
Relatively deep parts can be formed if the form able sheet is mechanically or pneumatically stretched prior to bringing it into contact with the mould surface and applying vacuum.
Suitable materials for use in vacuum forming are conventionally thermoplastics. The most common and easiest to use thermoplastic is high impact polystyrene sheeting (HIPS). This is moulded around a wood, structural foam or cast or machined aluminium mould, and can form to almost any shape. Vacuum forming is also appropriate for transparent materials such as acrylic, which are widely used in applications for aerospace such as passenger cabin window canopies for military fixed wing aircraft and compartments for rotary wing aircraft. Vacuum forming is often used in low-level technology classes for an easy way to mould.
Vacuum Forming of thermoplastic
Example of Vacuum formed products