Verify if a standard CNC setup can hit your target design constraints during the 3D modeling stage.
For broken edges, external radii, and chamfer heights, the permissible deviations for the m class are:
The K class tolerance equals the flatness tolerance for the shorter side of the angle.
Data source: ISO 2768-1:1989 standard
If you need help choosing between the classes for your specific product assembly. Share public link Tolerance Iso 2768 Mk Pdf
In conclusion, the Tolerance ISO 2768 MK PDF standard provides a set of general tolerances for linear and angular dimensions, which is essential in various industries. The standard ensures that parts and assemblies meet the required specifications, facilitating interchangeability and quality control. By understanding and applying the ISO 2768 MK standard, manufacturers can ensure that their products meet the required quality standards, reducing the risk of defects and rework.
Do you need to see how compares to tighter classes like Class f (fine) ?
German Institute for Standardization provides the same standards, which are widely referenced as DIN ISO 2768.
| Nominal Length Range of Shorter Side (mm) | Permissible Deviation | | :--- | :--- | | up to 10 | ± 1° | | over 10 up to 50 | ± 0°30' | | over 50 up to 120 | ± 0°20' | | over 120 up to 400 | ± 0°10' | | over 400 | ± 0°5' | Verify if a standard CNC setup can hit
The designation "ISO 2768" is split into two distinct parts that cover different geometric characteristics. The suffix tells the manufacturer exactly which tolerance classes to apply.
Practical Example: A 150mm long block machined flat does not need a flatness symbol. Under ISO 2768-K, its surface cannot deviate more than 0.2mm from perfect flatness.
When a drawing specifies , it is combining "Medium" (m) from Part 1 and "Class K" (K) from Part 2. Decoding "mk": The Precision Classes
Circular run-out limits the radial or axial variation of a rotating feature. Under Class K, the maximum allowable circular run-out is . Why Use ISO 2768-mk? Share public link In conclusion, the Tolerance ISO
Class k allows a maximum deviation of 0.2 mm . Why Use ISO 2768-mk in Design and Manufacturing?
Wrong. You must inspect them. If a drawing says "General Tolerance ISO 2768-mK" and you produce a part with a 1mm warp on a 100mm face, you have failed the K class (max allowed is 0.2mm). The part is non-conforming.
To apply these standards, simply add a note in or near the title block of your technical drawing: