General runout tolerance is always equal to the general tolerance for flatness (for cylindrical parts) or the larger of the two: flatness or perpendicularity. How to Read the Drawing Callout If a drawing says: GENERAL TOLERANCES ISO 2768-mK
In the world of mechanical engineering and CNC machining, precision is paramount. However, not every dimension on a technical drawing requires a tight, specific tolerance. Over-dimensioning a part can lead to skyrocketing production costs and unnecessary inspection time. This is where ISO 2768 becomes the silent hero of the workshop. iso 2768 general tolerances pdf exclusive
This saves inspection time, reduces phone calls about unimportant dimensions, and ensures your part functions as intended. General runout tolerance is always equal to the
If you are searching for the you are likely looking for more than just a standard document. You want actionable data, clear tables, and a deep understanding of how to apply these rules without purchasing expensive documents from standards bodies. Over-dimensioning a part can lead to skyrocketing production
| Nominal Size Range | f (Fine) | m (Medium) | c (Coarse) | v (Very Coarse) | | :--- | :--- | :--- | :--- | :--- | | 0.5 up to 3 | ±0.05 | ±0.1 | ±0.2 | — | | >3 up to 6 | ±0.05 | ±0.1 | ±0.3 | ±0.5 | | >6 up to 30 | ±0.1 | ±0.2 | ±0.5 | ±1.0 | | >30 up to 120 | ±0.15 | ±0.3 | ±0.8 | ±1.5 | | >120 up to 400 | ±0.2 | ±0.5 | ±1.2 | ±2.5 | | >400 up to 1000 | ±0.3 | ±0.8 | ±2.0 | ±4.0 | | >1000 up to 2000 | ±0.5 | ±1.2 | ±3.0 | ±6.0 | | >2000 up to 3000 | — | ±2.0 | ±4.0 | ±8.0 |
For a 100mm shaft (Class "m"), the tolerance is ±0.3mm. If you need tighter than this, you must specify the dimension individually (e.g., 100 +0.02/-0.00 ). Table 2: Angular Dimensions Angles (e.g., a 45° chamfer) have their own rules. The tolerance depends on the length of the shorter side of the angle.