: A detailed 4-page overview of ISO 20457 and DIN 16742 including classification tables.
Refers to dimensions affected by tool movement or parting lines. Key Concepts of ISO 20457
One rainy afternoon, a designer named Lila walked into the shop carrying a folded drawing of a new agricultural pump. Her company had outsourced molds for the past decade, but their latest prototype leaked at the coupling because of an overlooked tolerance. She had been told: come here; these folks care about fit. Ana read the drawing, checked the table, and proposed a blend of interference fit on the drive and a running fit on the bearing bore, with a specified surface finish to keep oil film intact. Lila watched as the team translated abstract values into toolpaths, cutters, and test assemblies.
Whether using injection molding, compression molding, or rotational molding, achieving high precision in plastics requires accounting for unique polymer characteristics like shrinkage, moisture absorption, and thermal expansion. 🛠️ The Purpose of ISO 20457
| 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 |
: A detailed 4-page overview of ISO 20457 and DIN 16742 including classification tables.
Refers to dimensions affected by tool movement or parting lines. Key Concepts of ISO 20457
One rainy afternoon, a designer named Lila walked into the shop carrying a folded drawing of a new agricultural pump. Her company had outsourced molds for the past decade, but their latest prototype leaked at the coupling because of an overlooked tolerance. She had been told: come here; these folks care about fit. Ana read the drawing, checked the table, and proposed a blend of interference fit on the drive and a running fit on the bearing bore, with a specified surface finish to keep oil film intact. Lila watched as the team translated abstract values into toolpaths, cutters, and test assemblies.
Whether using injection molding, compression molding, or rotational molding, achieving high precision in plastics requires accounting for unique polymer characteristics like shrinkage, moisture absorption, and thermal expansion. 🛠️ The Purpose of ISO 20457
| 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 |