Applying a metal‑part tolerance (e.g., IT6 or IT7) directly to a plastic part often results in a requirement that is impossible to meet or prohibitively expensive. DIN 16742 provides plastic‑specific tolerance tables precisely to avoid this mistake.
A key nuance in DIN 16742 is the distinction between dimensions formed within a single mold half () and those affected by the closing of the mold or moving slides ( non-tool-specified ). TG5 provides specific tables for both, usually allowing slightly more "give" for non-tool-specified dimensions to account for the mechanical play in the molding machine. Impact of Material Selection din 16742 - tg5
All tolerances are symmetrical ((\pm)). A practical minimum tolerance of is generally applied regardless of what the table might yield for very small nominal sizes. Applying a metal‑part tolerance (e
All tolerances in DIN 16742 are . If asymmetrical tolerances (e.g., fit dimensions) are required, they must be converted to a symmetrical tolerance field location by formally modifying the nominal dimension to the tolerance mean dimension C: 100-0.6 → 99.7 ± 0.3 . TG5 provides specific tables for both, usually allowing
Manufacturers must manage material shrinkage when producing plastic injection-molded parts. The German standard provides the global benchmark for determining dimensional tolerances. Within this standard, TG5 (Tolerance Group 5) represents a highly precise classification level. It balances tight engineering requirements with the physical realities of polymer behavior. 1. What is DIN 16742?