CASTING SOURCE

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SAND CASTINGS

CAST - MACHINED - FINISHED

Sand Casting is the oldest, most basic, simple, and cheapest method of casting ferrous and non-ferrous materials and alloys. In the sand casting process, a pattern is made in the shape of the desired part. The pattern can be made in wood, plastic, or metal. Simple sand casting designs can be made in a single or "solid pattern". More complex sand casting designs are made in two parts, called "split patterns".

The sand casting patterns are then packed into sand, mixed with a binder, which helps harden the sand in to a semi-permanent shape. Once the sand mold is cured, the pattern is removed, leaving a hollow space in the sand in the shape of the desired part. The pattern is intentionally made larger than the cast part to allow for shrinkage during cooling. Cores can be inserted into the mold to create holes and improve the sand casting's net shape.

The pouring temperature of the material should be a few hundred degrees higher than the melting point of the material to assure good fluidity, thereby avoiding premature cooling, which can create voids and porosity. When the material cools, the sand is removed and the sand casting is ready for secondary operations, such as machining and finishing.