Q. What is vacuum forming?
A. Vacuum forming is a plastic thermoforming process that involves forming thermoplastic sheets into three-dimensional shapes through the application of heat and pressure. In general terms, vacuum forming refers to all sheet forming methods, including drape forming, which is one of the most popular. Basically during vacuum forming processes, plastic material is heated until it becomes pliable, and then it is placed over a mold and drawn in by a vacuum until it takes on the desired shape.
Vacuum thermoforming is a great method for producing plastic parts that have sharp details and fit nicely to specific products.
Q. What are the limitations in vacuum forming?
A. Vacuum forming is usually – but not always - restricted to forming plastic parts that are rather shallow in depth. Thin sheet is formed into rigid cavities for unit doses of pharmaceuticals and for loose objects that are carded or presented as point-of-purchase items. Thick sheet is formed into permanent objects such as turnpike signs and protective covers. Relatively deep parts can be formed if the formable sheet is mechanically or pneumatically stretched prior to bringing it in contact with the mold surface and before vacuum is applied.