Editing Metal casting (section)

===Shell molding===
{{Main article|Shell molding}}

Shell molding is similar to sand casting, but the molding cavity is formed by a hardened "shell" of sand instead of a flask filled with sand. The sand used is finer than sand casting sand and is mixed with a [[resin]] so that it can be heated by the pattern and hardened into a shell around the pattern. Because of the resin and finer sand, it gives a much finer surface finish. The process is easily automated and more precise than sand casting. Common metals that are cast include [[cast iron]], aluminium, magnesium, and copper alloys. This process is ideal for complex items that are small to medium-sized.