General Tolerance Iso 2768-mk -
Defines the tolerance class for linear and angular dimensions (Medium).
| Nominal Length Range (mm) | Class f (Fine) | Class m (Medium) | Class c (Coarse) | Class v (Very Coarse) | | :--- | :---: | :---: | :---: | :---: | | | ±0.05 | ±0.10 | ±0.20 | — | | 3 up to 6 | ±0.05 | ±0.10 | ±0.30 | ±0.50 | | 6 up to 30 | ±0.10 | ±0.20 | ±0.50 | ±1.00 | | 30 up to 120 | ±0.15 | ±0.30 | ±0.80 | ±1.50 | | 120 up to 400 | ±0.20 | ±0.50 | ±1.20 | ±2.50 | | 400 up to 1000 | ±0.30 | ±0.80 | ±2.00 | ±4.00 | | 1000 up to 2000 | ±0.50 | ±1.20 | ±3.00 | ±6.00 | | 2000 up to 4000 | — | ±2.00 | ±4.00 | ±8.00 |
Imagine a shaft with a nominal diameter of and a length of 200 mm .
Even when ISO 2768 is invoked, some dimensions are typically excluded. General tolerances do apply to the following: general tolerance iso 2768-mk
Linear dimensions include external sizes, internal sizes, steps, diameters, and distances. Nominal Size Range (mm) Permissible Deviation (mm) for Class Over 3 to 6 Over 6 to 30 Over 30 to 120 Over 120 to 400 Over 400 to 1000 Over 1000 to 2000 Over 2000 to 4000 External Radii and Chamfer Heights
ISO 2768-1 defines four tolerance classes: f (fine), m (medium), c (coarse), and v (very coarse). The "m" designation means your design will follow medium tolerance limits.
Press fits, slide fits, and bearing journals require tolerances far tighter than the ±0.1 mm to ±0.3 mm provided by the "m" class. These always require explicit limit dimensions or GD&T (Geometric Dimensioning and Tolerancing) callouts. Defines the tolerance class for linear and angular
Section A
Governs geometrical tolerances (e.g., straightness, flatness, perpendicularity, and symmetry). The Four Tolerance Classes for Linear Dimensions (Part 1)
6 to 30 mm: ±0.5 mm
represents the gold standard for general tolerances in modern mechanical engineering. It harmoniously blends the 'medium' linear tolerances with 'medium' geometric controls to produce parts that are both functional and economical.
General tolerances for circularity and total run-out are often handled by the same principles as the straightness/flatness of the related surfaces. KEYENCE CORPORATION OF AMERICA Application & Implementation Drawing Note:
