Green Sand Casting
The standard sand casting procedure that we implement for our bronze and aluminum castings is the green sand molding method. With this method the sand, which is mixed with a binder, is packed around the pattern to produce the mold. This is done by hand with pneumatic tools or with our automated sand machine known as a hunter. The patterns are removed from the mold leaving a cavity that will later provide the parts geometry. If the part being cast needs to be hollow or has areas of undercut, a core is used to provide the internal features. One of the great things about the green sand method is that no baking or chemical treatment is required to get the mold to its final state so the cost and time between a finished pattern and a finished part is greatly diminished.
Permanent Mold Casting
For higher volume orders we implement permanent mold tooling to combat the price per part for aluminum castings. Given a large enough production run permanent mold tooling can pay for itself and minimize lead times. As opposed to packing sand around a pattern to create the cavity for the part, a piece of iron is milled to the appropriate geometry to produce the mold. Once the mold is produced it can be indexed into a vault and pulled anytime the part needs to be run. Whenever possible multiple cavities are machined into a single mold to maximize the number of parts per pour. A single permanent mold can yield thousands of parts and can do so with great consistency. The surface finish and tolerance is comparable to that of die casting.
No Bake Casting
The no bake or air set process consists of packing sand mixed with a urethane binder around a pattern which solidifies to create the final mold. No bake molds provide a great surface finish and can withstand the demands of our largest castings.