Shell-mold casting
Shell-mold casting yields better surface quality and tolerances. The process is described as follows:
โ The 2-piece pattern is made of metal (e.g. aluminum or steel), it is heated to between 175ยฐC-370ยฐC, and coated with a lubricant, e.g. silicone spray.
โ Each heated half-pattern is covered with a mixture of sand and a thermoset resin/epoxy binder. The binder glues a layer of sand to the pattern, forming a shell. The process may be repeated to get a thicker shell.
โ The assembly is baked to cure it.
โ The patterns are removed, and the two half-shells joined together to form the mold; metal is poured into the mold.
โ When the metal solidifies, the shell is broken to get the part.
Making the shell-mold |
Shell mold casting |