ISO 2768‑2 gives recommended tolerances for flatness, straightness, circularity, cylindricity, etc., corresponding to the same f/m/c/v classes. However, ISO 2768‑2 is limited and cannot replace proper GD&T where function requires control of form, orientation, runout, or position.
Pitfalls:
30 — 120: ±0.3
ISO 2768‑1 also provides default angular tolerances (e.g., ±1° for coarse grades, ±0.5° for medium — see the standard for exact figures) and for unspecified radii/chamfers.
The ISO 2768-MH tolerance chart provides a set of tables that list the tolerance values for different types of dimensions, including linear dimensions, angular dimensions, and geometric tolerances.
Do not use ISO 2768 when: