Investment Casting Services

Fathom offers metal casting prototype services in a variety of materials including magnesium, aluminum, zinc, and bronze, which are created with a plaster, sand, investment or permanent molding process. 

The Process

1. A master model is created from the master mold
2. The master molds are used to generate plaster molds
3. The mold is left to dry (typically 3-5 days)
4. The metal is poured into the plaster mold
5. The final product is cleaned and prepped for shipping or machining

Wax is injected into an aluminum die to produce a pattern that is an exact replica of the part to be produced. For every casting, a wax pattern must be manufactured. The patterns are clustered around a coated sprue and repeatedly dipped into an agitated vat of ceramic and allowed to dry. After a shell thickness of approximately 3/16″ has been built, the molds are dewaxed by either flash firing at high heat (1,400° F.) or autoclaving (pressure and steam). The hollow shells are then preheated to 800-2,000° F, depending on the alloy to be poured. The molten metal is immediately cast into the hot shell. After the metal parts have cooled, the ceramic is vibrated, blasted off and discarded. The balance of the cleaning operations (cut off, grind, heat treat, straightening & blast) are straightforward and quite similar to the other casting processes.