The investment casting process, like other casting processes, is not too hard to understand. The analogy I like to use when explaining it is the clay dough analogy. Imagine that you’ve got a piece of clay dough, and you pick it up with both hands. If you squish the dough together and then pull your hands straight apart, out will fall a piece of clay dough that is shaped like the space between your hands and is imprinted with the mirror image of the surface of your hands. This is what casting is – forming something within something else.
Why are there so many kinds of different casting processes? There are a few answers to this question. The first answer is also the most important one: casting is used to create all kinds of different products in all kinds of different shapes and sizes. A process like sand casting wouldn’t be ideal for the large scale production of many identical products because only one product can be made at a time, and each product must be made by hand. This makes it a time-consuming and labor-intensive process, but it can be used to create products that other casting processes are incapable of producing. Investment casting is similar to sand casting in that the investment casting process is used to create detailed workpieces in relatively small quantities, and for this reason it can be unsuitable for certain casting operations.
Each casting process is uniquely suited to its application, though there is some crossover in terms of each process’s suitability for the creation of certain kinds of products. Generally speaking, though, investment casting is used to create a certain kind of product, die casting is used to create another certain kind, and so is sand casting, slip casting and so on and so forth. The investment casting process, like all other casting processes, is best reserved for the creation of certain kinds of parts and in certain quantities.