Gussform

Gussform, literally “casting mold” in German, refers to a hollow cavity used to shape molten metal or other materials as they cool and solidify. In metal casting, a Gussform is created by packing or assembling mold material around a pattern that defines the external shape. Once the pattern is removed, the mold cavity is ready to receive molten metal. Gussformen can be single-use (produced from sand or plaster) or reusable (metal molds), depending on material and process.

Common mold types include sand molds (green or dry sand used in traditional foundries), ceramic-shell or investment molds for precision parts, plaster molds for light alloys, and permanent metal molds used for high-volume production. Investment casting uses a wax pattern embedded in refractory material to create a negative cavity after the wax is melted away. Core inserts may be used to form internal passages or undercuts.

Key components of a mold system are the pattern, the mold material, the gating system (sprue, runners, gates) that controls the flow of metal, and optional cores for internal features. Mold design must account for shrinkage, porosity, and surface finish, as well as ease of demolding.

Process overview: a pattern is used to form the mold, the pattern is removed, the mold is assembled (if needed), molten metal is melted and poured into the cavity, the metal is allowed to cool and solidify, and the finished casting is ejected and finished (trimming, grinding, heat treatment). Safety and quality steps include venting, riser design to prevent defects, and inspection.

Gussform use spans heavy industry, jewelry, sculpture, and dental casting, reflecting its central role in producing replicable shapes from a broad range of materials.