GB/T 42124.3-2025 has replaced GB/T 6414-2017. This article compiles the tolerance tables for DCTG4-DCTG10, recommended grades for investment casting, GCTG geometric tolerances, and RMAG E machining allowances based on the official standard text.

Machining allowances in precision casting are not fixed values. This article explains how to determine the machining surfaces and allowances for stainless steel castings from blank to CNC finished product, starting from machining datum, casting structure, dimensional tolerances, deformation risks, and clamping methods.