Process and mould for casting fragile and/or complex shapes.

摘要

@ A method and apparatus for casting articles of complex and/or fragile shapes, involving the formation of a two-layer wax mould (24) about a deformable rubber pattern of the shape to be cast. The pattern is dipped into a bath of molten water-insoluble wax to form a first layer (20) of wax thereon, and thereafter a second layer (22) of water-soluble wax is formed around the first layer (20) by dipping or otherwise.

The pattern is then removed from the two-layer mould (24) by means of a puller acting on a base plate (16) secured to the rubber pattern. The outer layer (22) of wax provides support forthe thinner inner layer (20) containing the casting impression during the extraction of the pattern, preventing impairment of the impression. The outer layer (24) is then dissolved away in water leaving the inner layer (20) as a thin wax mould into which slip of casting material is poured and allowed to solidify. The inner wax layer (20) is than completely removed from the cast article by means of an organic solvent.