The history of vacuum casting

One of the first relatively simple vacuum casting systems with manual mixing and tilting unit.

During the sixties the technology of plastic casting under vacuum using a silicone mould was developed, at the Technical Universities of Dresden and Cottbus in the former German Democratic Republic.

As no one realised the advantages of the system in Europe, the technology was sold to Japan in the seventies, where it was mainly used in the automotive industry. The curious fact is that from there it came back to Europe and Germany, and meanwhile it can be found in the development department of nearly every large production company.
On principle, this process is the combination of conventional, well-known technologies:

An Italian machine with injection into the vacuum from outside by means of a cartridge gun.

Casting by in-gate and risers has been practiced since the Bronze Age, i.e. since more than 3.500 years. Also vacuum has been used for several thousand years. Cupping, for example, was achieved by means of prepared cow horns, which, after having been attached, were either sucked in with the mouth and sealed with wax, or a vacuum was produced  by burning down  alcohol-soaked wool flakes  within the horn. Flexible moulds, for example made of natural caoutchouc, have also been used for many years, by restorers and sculptors among others, in order to make moulds of reliefs or sculptures  without disturbing them.
This Japanese machine with the characteristic bull’s-eyes is the precursor of all modern vacuum casting systems.
The combination of these three techniques in conjunction with thermosetting plastics, which were developed in the eighties, represents the main advantage of this procedure. It led to the breakthrough, allowing the two-component-resins, to imitate materials used in large series production as polypropylene and polyethylene in a practically identical way.
Based on this concept, further processes, automation and accessories were developed, which guaranteed a simple, fast and cost effective handling of the system.