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The ceramic shell casting process starts with wax injection. A die or tool is filled with wax that is injected in a liquid or a paste form so it flows into the detail of the mold. Once cooled,
the wax piece - a pattern - is removed from the die.
Several wax patterns are attached to a wax pole - commonly called a “sprue”. Each pattern is attached to the sprue by smaller pieces of wax runners which are typically referred to as
“gates”. Gates allow for the eventual creation of a space where molten metal can flow into the hollow pattern cavity. The complete assembly is referred to as a “tree”.
The next step involves coating the wax tree in a slurry. Slurry is a mixture of liquid binder and flour materials. Depending on the alloy being cast, drying time requirements, and number of
coats desired, the binder and flour materials used may vary.
Once the tree is dipped in the slurry material, and excess material is drained from the tree, it is then coated with sand - commonly referred to as “stucco”. This can be done in a variety
of ways including: rainfall sanding, use of a fluidized bed, or by hand covering (the “cat box” method).
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