You must obtain the metal shrink rate from your selected foundry and incorporate it into the pattern. If for example, you are producing a 10 in. (254 mm) aluminum pattern and the foundry recommends a .5% shrink rate (.005 in. per inch), you must increase your database 100.5% to produce a pattern that is 10.050 in. (255.3 mm) to allow for the .050 in. (1.3 mm) shrinkage of the material.
Based on the geometry, the foundry may ask for a different rate in each axis. Do not assume that the shrink rate from one foundry is the same as another foundry. Many variables, primarily gating methods, can have dramatic effects on metal shrinkage.
The easiest place to add the foundry’s shrink rate is in the 3D Sprint software.