Reliance Foundry Blog

Foundry Sand

A pile of different sized green and yellow olivine crystals sits on a plain background

Molding sand is at the heart of the sand casting process. It must hold a shape well and capture the fine details of a casting, yet be permeable enough to allow gases to escape. Under the strain of having the molding pattern removed from it, or while it is filled, it cannot crumble or sink on itself. When it is turned upside down it must not lose its form: the parts of a mold have to stay true while clamped together.