- Pressure Forming is a sophisticated version of the vacuum forming process utilizing air pressure as a forming aid to increase the detail on the mold side. Features that could not be achieved by vacuum alone can be molded with pressure forming. The result is a product with the look and feel of an injection or structural foam molded part at a price close to a vacuum-formed one.
The mold makers start by creating a pattern based upon drawings and specifications of the custom part. From the pattern, these craftsmen produce either a hardwood or aluminum mold. A wooden mold is used mainly for a customer required prototype or a very low volume production run. The aluminum mold is used for a full production run and when the pressure forming process is necessary.
The pressure forming technique provides for forming heavier sheet from 0.093" thick up to 0.375" thick. The technique is accomplished by forcing a hot sheet against a mold, usually female, by introducing compressed air to the back side of the heated sheet. This method will provide as much as 75 psi working on the sheet surface as compared to the 14 psi in vacuum forming.