Designing for molding

Principles of sand molding.

Good design of a casting successfully combines the requirements of its end use and those of its production processing. Among the significant casting production costs are those associated with molding and gating and risering. Mold designs must avoid overhangs or undercuts that will prevent pattern removal from the mold. The illustration to the left shows a typical sand mold after the pattern halves have been removed. Also shown is a split pattern used to produce the sand mold cavity, the cylindrical core used to make the hole through the casting, and the "rough" casting as it is shaken out.