Casting Geometry Permanent mold castings can have an abundance of external features. Cores may be used to provide internal shape. A wide range of dimensions are possible. A flat parting line is preferable for economical mold construction and operation. Draft angles prolong mold life and facilitate part ejection from the mold.
Round parts can utilize natural contour as draft.
Draft stock can be made functional. Tolerances and Finish Stock Dimensional capability varies with casting geometry and tooling condition. Special would be possible in areas of favorable geometry with precision tooling and increased erosion control. Tighter dimensions may be possible by initial grinding at the foundry. Machining benefits and soundness of permanent gray iron castings are based on metallurgical factors.