If you need something crafted from aluminum, you may be surprised to learn that there are a couple of different methods for casting your item. Two of those methods, sand casting and die casting, produce equally good results depending on what you want to create. If you are unfamiliar with one or both of those methods, or why you might select one method over the other, the following information should help.
Sand casting is a fascinating method of molding your object. Liquid aluminum is poured into a mold that is comprised of dense, wet sand that has been carefully sculpted (like a sand castle) to create the exact shape of your item. Typically it is used to create two halves of the same thing, and then fuse them together later because the sand mold may be unable to hold its shape while the liquid aluminum is poured into it. If the sand is mixed with a clay, then the two halves may be secured together before the liquid aluminum is ever poured into the mold. If you want to make something out of aluminum, and you want to do it as inexpensively as possible, then you might choose sand casting for the process.
Die casting is creating a metal object from a metal mold. The liquid metal may be hot or cold, extruded or injected and the objects made from it always need some sanding or refinishing because there will be small seams of metal sticking out from around the object. Die casting is best used for aluminum items that you want to manufacture quickly and in mass numbers. It is more expensive because it is more precise and less likely to create several failed attempts and flawed items (which can happen with the sand if the sand or sand and clay mixtures do not hold their shape throughout the molding process).
When You Might Use One Process Over the Other
When you want to exert more control over the outcome of of your aluminum casting and money is not an issue, you would use the aluminum die casting process. In many cases the die casting mold can be reused repeatedly with consistent results (e.g., you want to mass-produce children’s toy cars out of an aluminum alloy and need to make sure they are all alike). On the other hand, if you just need to create a handful of near-exact items and you want to keep it cheap, you would use the sand casting process (e.g., you want to make some aluminum prototypes to show company executives what could be done to improve upon current machinery components).