TG5 assumes dimensional stability at 23°C / 50% RH. If your part operates at 80°C in PA66, the tolerance must be loosened by 25% due to creep—or switch to glass-filled material.
TG5 represents the widest range of permissible tolerances defined in the standard tables. It is designated for applications where high precision is not critical to the function of the part, or where the material properties make tighter tolerances economically unviable.
Key characteristics include:
DIN 16742 - TG5 is not a single number. It distinguishes between three tolerance categories:
The selection of TG5 is typically driven by the material choice and the part geometry. din 16742 - tg5
You do not need TG5 on a cosmetic snap-dome button. Apply TG5 only to critical features (bearing diameters, mating bosses, gear centers). Use TG4 for all other dimensions.
DIN 16742 defines four tolerance grades for plastics: TG5 assumes dimensional stability at 23°C / 50% RH
The key feature of TG5 is that it is the highest (strictest) precision grade in the standard, requiring the most accurate molds and stable processing conditions.
Do not default to TG5. Specify it only for: The key feature of TG5 is that it
To check compliance with DIN 16742 TG5: