Jack Liu 0 Report post Posted September 1, 2011 From "Wikipedia" The process starts by placing a two piece silicone mold in a vacuum chamber. The raw material is mixed and degassed and then poured into the mold. The vacuum is then released and the mold removed from the chamber. Finally, the casting is cured in an oven and the mold removed to release the completed casting. The silicone mold can be reused.[3] In some machines the chamber where the material is mixed a pressure can be applied to increase the pressure differential between the mold cavity and the mixing chamber. Share this post Link to post Share on other sites