Sand-Casting Mold Making Information

Whether it¡¯s engineers creating machine components, hobbyists replicating vintage parts or artists stretching their imaginations, sand-casting is a versatile process to make single-use molds for casting metal. With the right materials and precautions, sand-casting is fun, safe and effective.

Mold-Making Sand

1. Sand-casting isn¡¯t done with common beach sand. It¡¯s a specialized natural or synthetic product with a very fine and even grain. The finer the grain, the smoother the finish on the casting. The sand is mixed with oil and clay so it packs tightly and maintains its shape. The mold may also be cured by adding a chemical catalyst. "Green sand" means the sand is not cured by heat or chemical reactions.

   Casting Metals

2. The most common metals used in sand-casting are aluminum, bronze, pewter, and tin alloys. The choice is dictated by the application, the caster¡¯s skill and the type of furnace available. Pewter and tin alloys are favored by hobbyists and jewelry makers for appearance and low melting point of around 200 degrees Celsius. Most engineering applications use aluminum, which has a melting point of 600 degrees Celsius.

   Safety

3. Safety is critical when handling molten metals. Eye protection should be worn. When melting and pouring molten metals, the caster should wear shoes, long pants and long sleeves.