Flask Technology

This casting technology was originally developed for the jewellery and dental industries, for the production of comparatively small parts. As the production time is relatively short compared to conventional shell building, it is also being applied more and more for Rapid Prototyping.  In the embedding machine a chalky powder is mixed with water under vacuum and poured over the wax part, housed in a small metal container, the so-called flask.

After solidification of the plaster, the flask is heated to a casting temperature of 300 – 500 °C, step by step. It is then cooled down depending on the material.

After the cast the part is de-bedded by means of a high-pressure water-jet to release the part from the plaster. The part is then sent for finishing.

ADVANTAGES

  • Very good surface quality
  • Material is only mixed if required
  • No cores are necessary
  • Easy debedding with water

DISADVANTAGES

  • Only small and medium-sized parts are possible
  • Only low melting alloys e.g. aluminium can be cast, no steel
  • High material usage and lots of waste
  • No perfect casting quality because of the long solidification process, depending on the size of the flask
  • Burning takes up to several days, depending on flask size
  • Oven is blocked for many hours / days with (one) flask, as soon as the tempering process has been started