Shrinkage allowance in investment casting is often presented as a single percentage added to a model. That is a convenient introduction, but an incomplete tooling strategy. The finished dimension reflects several stages of the process and the way a particular feature behaves within the component.

Printed expendable patterns can change the early economics of investment casting by offering a route that does not begin with conventional pattern dies. They are especially worth evaluating when geometry is still developing. However, removing a tooling step does not remove the need to qualify the mold and metal-processing route.

Gating delivers metal into the casting cavity. Feeding supplies metal where needed as the casting solidifies. Although these functions interact, solving a filling problem does not automatically solve a shrinkage problem. Gating and feeding design should therefore be evaluated as part of the complete solidification route.