Lost Wax Casting & Finishing

Mold Making: Rubber is heated under pressure and flows around the prototype making a mold. When cool it is then is cut apart leaving a cavity in the rubber in the shape of the original piece.

Wax Injection: Molten wax is injected into the rubber mold creating a wax copy of the original.

Sprueing: The wax is attached to a rubber base with a number of others.

Investing: The wax is surrounded by a metal cylinder called a flask which fits onto the rubber base. This cylinder is then filled with plaster which has been mixed under vacuum to draw out the air it contains. The plaster encases the wax pieces and then hardens. The base is removed and the assembly is placed in a kiln.

Burnout: The flasks with the plaster encased waxes are heated overnight to 1350 degrees which burns away the wax leaving cavities in the plaster in the shape of the original pieces.

Casting: Metal is melted and poured into the flask. A vacuum system again helps remove trapped air and gases.

Desprueing: The plaster is broken off the pieces which are then cut away from the base and cleaned.

Hand Finishing: The pieces are sanded and filed to remove traces of the sprue, mold lines and any imperfections.

Tumbling: Pieces are oxidized if required and undergo a multiple step tumbling process using different grit media to achieve the final desired finish.