The investment casting process enables excellent, repeatable as-cast tolerances. Castability of +/- three standard deviations - typically +/- .003 to +/- .004 per inch when individual spot measurements are repeated. This may vary from part design to part design as tolerance capability is largely affected by part configuration. However, symmetrical shapes with uniform wall sections solidify with significantly less change than inhomogeneous and asymmetric wall sections.

Linear Tolerance Normal linear tolerances for normal dimensions reflect these three sources of variation: Prediction of parts and shrinkage factors (20%) Diemakers and tools, tolerances (10%) Process variation (70% of linear tolerance)

Variation in investment casting tolerances is a combination of part configuration effects that cause non-uniform shrinkage, and all other process variations in producing wax patterns, ceramic molds, and castings.