| Tolerance Class | Permissible Deviation (mm per 100mm length) | | :--- | :--- | | Fine (f) | ± 0.3 mm/m | | Medium (m) | ± 0.5 mm/m | | Coarse (c) | ± 1.0 mm/m |
The is not just a chart of numbers – it is a philosophy of realistic tolerance allocation for plastics. By adopting this standard, you will reduce tooling costs, lower inspection fallout, and improve assembly reliability. iso 20457 tolerance table pdf
Unlike metal machining tolerances, plastic parts require special consideration due to material shrinkage, warpage, moisture absorption, and processing conditions. ISO 20457 addresses these variables by providing tolerance classes that account for the complexity of the plastic material and the moulding process. | Tolerance Class | Permissible Deviation (mm per
You can purchase the official standard from national bodies: ISO 20457 addresses these variables by providing tolerance