The main cause of failed casting in our shop is included investment. The principle cause of included
investment is the design of the wax. Included investment occurs when a piece of investment breaks
off and floats in the molten metal. This is usually caused by holes, slots or sharp angles in the wax that leave fragile pins or blades of investment, after the wax is burned out. These fragile pieces of investment can break off when hit by fast-moving, molten metal.
Bottom Holes
Pre-drilled pave holes and holes for bracelet hinges create pins of investment that can break if they are too thin in relation to their diameter.
