Nicerapid – The Concept Of Vacuum Casting

An exceptionally economical way of creating a prototype isvacuum casting. This method of duplication was developed in the late 60s in Germany.Vacuum castingis quite similar to duplication by the usage of silicone moulds.

This process is suitable for elastomers and employs the usage of vacuum to draw liquids to the mould. This process is best suited in conditions where there are minute details or the mould is made up of fibre or any type of reinforced wire.

It is also known as thermoforming as it requires preheating plastic sheets to contribute to the rapid prototyping of the manufacturing process. To make the materials soft, they are preheated in a vacuum casting machine which is automated.

The Procedure behind Vacuum Casting

Setting a Master Model

To initiate this process, there is a requirement of a high-quality reference model. This model could be the industrial part or any model made by stereolithography. This model should encapsulate the precise dimensions and appearance one deems correct. This is necessary to ensure the absence of flaws in the prototype on the completion of the process.

Moulding

This model is encased in a rubber mould, which is two-part and mostly silicone. This is then treated to high temperatures to facilitate the sticking of the two parts. This ensures that the mould is strong and resilient for higher durability.

The mould is then cut apart to get a glance of the central hollow space, which should have the same dimensions as the master reference model. The division of the mould into two parts is followed by its placement inside the vacuum chamber. Further on into the process, the suitable material is filled into the mould to give shape to the final product.

Process of filling Resin

The mould needs to be filled with suitable material. This material should replicate the features and quality of the industrial material. This resin is generally mixed with powders of metals or pigments to enhance its functional properties or achieve a certain specification.

After this process is done with, it has to find a placement in the vacuum chamber. This is to ensure the absence of bubbles. This is crucial to avoid any kind of damage to the final product.

Curing Stage

Finally, the resin is kept in the oven. It is subjected to high temperatures to ensure the durability of the material. Further, the silicon mould is taken away to find usage in the preparation of more prototypes.

After the removal of the prototype, it is prepared for the final look. This might involve painting and decoration. This is done to maintain the aesthetic quality of the product and ensure that the product achieves a sleek look.

Therefore,vacuum castingoffers great versatility in the production of parts ranging from nylon to polyurethane which can replace other polymers for the creation of prototypes and other parts. This technique is best suited for low volume production.

Charles Brown