• The casting design engineer always optimizes his casting design, balancing benefits versus costs and considering how complex features can be produced in the casting.

• In the perfect situation, the casting can be produced in net-shape, with every feature produced in the mold and no finish machining required.

• In the real world,  increased mold complexity and cost have to be compared against the costs of  rough and finish machining, considering the required production volume.

Special features in castings are often produced by additional removable mold components, commonly called "cores."