To enforce these rules, place the designation in or near your drawing’s title block. Combine the letters from Part 1 and Part 2. For example, indicates: m: Medium general tolerances for linear/angular dimensions. K: Medium general geometrical tolerances. When NOT to Rely on ISO 2768 General Tolerances
If a drawing indicates compliance with ISO 2768-2, features are automatically toleranced for:
The official standard documents can be obtained from national standards bodies such as ANSI, DIN, or directly from the ISO store. For a quick reference, CNC machining and engineering resource websites often provide free summary tables and charts summarizing the key tables from the standard, but these should not be used as a substitute for the official standard in a professional setting. The standard is also available in downloadable PDF format for purchase. Iso 2768 General Tolerances Pdf
ISO 2768 is widely used across manufacturing industries to ensure consistent interpretation and application of tolerances.
| Shorter Side Range (mm) | f (Fine) | m (Medium) | c (Coarse) | v (Very Coarse) | |------------------------:|:--------:|:----------:|:----------:|:---------------:| | ≤ 10 | ±1° | ±1° | ±1°30′ | ±3° | | over 10 up to 50 | ±0°30′ | ±0°30′ | ±1° | ±2° | | over 50 up to 120 | ±0°20′ | ±0°20′ | ±0°30′ | ±1° | | over 120 up to 400 | ±0°10′ | ±0°10′ | ±0°15′ | ±0°30′ | | over 400 | ±0°5′ | ±0°5′ | ±0°10′ | ±0°20′ | To enforce these rules, place the designation in
Using a globally accepted ISO framework removes language barriers between domestic design firms and overseas manufacturing vendors.
This comprehensive guide breaks down everything you need to know about ISO 2768 general tolerances, how to interpret its tables, and why having an ISO 2768 general tolerances PDF reference sheet is essential for modern machine shops and design departments. What is ISO 2768? K: Medium general geometrical tolerances
ISO 2768 is a foundational international standard used to simplify engineering drawings by defining general tolerances
While Part 1 handles length and width, Part 2 handles the "shape" and "orientation" of a part. It uses three tolerance classes: Geometric Characteristics Covered:
Reduces visual clutter, making blueprints easier to read.
If you tell me (e.g., sheet metal, CNC turned, cast), I can recommend the best ISO 2768 class to use. I can also help you interpret specific GD&T symbols if you have questions! General Tolerance - ISO 2768 1 & 2 - ZEISS Quality Forum