What is vacuum forming?
Simply put, vacuum forming is the process of taking a flat sheet of plastic and changing it into a contoured shape. This is achieved by clamping a sheet of plastic in a frame and heating it until it becomes soft and flexible.
The heated sheet is then stretched over a mould and the air is removed from underneath the mould cavity allowing atmospheric pressure to force the plastic over the mould. The plastic sheet then takes the shape of the mould. The plastic is then cooled to retain it's shape and finally removed from the mould and trimmed as required to create a finished part.
The Benefits of Vacuum Forming
· One-piece construction
· Economical tooling low mould and tooling costs
· Weight reduction [as compared to metals]
· Short lead-time
· Thin and thick walled properties
· Relatively low forming forces
· Finish and color flexibility
· Short cycle times
Vacuum Forming Advantages
Vacuum forming offers several processing advantages over other forming processes such as rotational, blow and injection moulding. Because of the low forming pressures used, low cost tooling can be utilised also making it economical to fabricate large parts. Moulds can be made of relatively inexpensive material, can be made in house and in a very short time. This can result in short lead times and makes it economical to run prototypes, small runs and one off custom jobs.