The lookup table tblGtolProcessCapabilities lists the geometric tolerance grade and roughness ranges achievable by a given process for a given type of tolerance/roughness. A tolerance grade range together with a feature size determines a literal tolerance range. See the section “How aPriori calculates achievable tolerance ranges” in the aPriori Professional User Guide.

Tolerance and roughness ranges affect cycle times, and help determine which features require specialized finishing operations. See the Tolerances and Finishing Operations section of the Design to Cost tab.