Vacuum Casting

Vacuum casting is a process for producing multiple models and prototypes which can be used for form, fit and function testing. This process can be utilised for small batch production dependant on size and material requirements.

A master model is required initially which is used to form the cast or mould. These are usually created by the use of the SLA process (as we talked about before). Once the master model is produced it is used to create a silicone mould or tool that can be used to manufacture multiples of cast parts.

The casting material of choice is poured into the mould, to ensure that any trapped air is removed from the cast resin; this process takes place within a vacuum chamber. Any trapped air would potentially cause distortion to the finished part. Once the casted part has dried sufficiently it is then removed from the mould. The mould can be re-used a number of times before a replacement would be required.

This process accommodates a wide range of plastics and polymers which can be selected to most closely mimic the thermoplastic production material. Materials offered include ABS and Polypropylene type materials; it is also possible to include some form of additives.

Advantages:

·  Parts are accurate to design

·         Repeatability

·         Texture and colour options

·         Various high quality finishing options

Disadvantages:

·   Limited mould life

·         Can be expensive

·         Limitation to material options