Unlike geometric dimensioning (GD&T), DIN 16742 - TG5 uses combined with material-dependent shrinkage. The standard provides tables, but the logic is as follows:
The ability to maintain TG5 tolerances depends on several manufacturing variables outlined in the standard: Material Shrinkage
mm (values vary based on whether the dimension is "tool-specified" or "non-tool-specified"). Tool-Specified vs. Non-Tool-Specified Dimensions din 16742 - tg5
| TG level | Typical use | Relative cost | Mold precision needed | |----------|-------------|---------------|------------------------| | TG1–TG2 | Medical, optical, micro parts | Very high | Precision tooling, hard steel | | TG3–TG4 | Precision fits, moving parts | High | Good toolmaking | | | General mechanical parts | Standard | Standard CNC mold | | TG6–TG7 | Non-critical covers, spacers | Low | Less precise mold |
The primary technical feature of TG5 is that it does not use a single percentage for all dimensions. Instead, it splits tolerances into and Non-Functional Dimensions (N) : Unlike geometric dimensioning (GD&T), DIN 16742 - TG5
: It often yields a minimum tolerance of approximately ±0.1 mm for smaller features, with general tolerances scaling around 0.4% – 0.5% of the nominal dimension.
On a technical drawing, you can write:
Parts where functional fit is important but doesn't require extreme sub-millimeter precision.
