The original piece is usually lost after the construction of the mold. This is normal and if you do want to prevent this from happening you can create the original from material other then wax like a metal alloy. When the mold is ready you are then going to pour molten wax, you’re not ready for metal just yet, into the mold. The amount of wax needed for this step depends on the desired thickness. Once the copy is ready, you are going to remove it very carefully from the mold. You will remove any of the impurities from the copy. This is called chasing. You will then sprue the copy. Spruing is the act of carefully placing paths that will let the molten metal in and air out. Afterwards, a ceramic shell is created around the copy. The shell isn’t really ceramic but a combination of liquid silica and sand.
Traditionally, and in some areas still, animal dung and dirt is used to create the shell. The choice of which shell material you want to use is up to you. The shell is hardened in the kiln and the wax melts out. If you want to reuse the wax then collect it during this step. Wax can be reused a number of times and if you are on a budget or are just trying out different designs and methods, collecting the wax is encouraged. Once the wax is gone and all that remains is the hollow shell you will want to run water through it to make sure there are no leaks.
If there are then you will need to patch them before pouring the molten metal. You are going to want to reheat the shell before pouring the metal to avoid shattering the shell. The shell is still on the sprue tree so pouring the metal is an easy process. When the metal has hardened, then break the shell carefully and remove the cast. Afterwards, it is up to you to finish the piece to your liking and preference.
The casting process is an enjoyable experience but it does use a few tools that you might need to purchase before hand, like the wax and spruing tree. At the very least, you might want to try Lost Wax Casting once or twice to get a feel for it. This way you have another casting process at your disposal.
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