standard is a critical German guideline for determining tolerances for plastic moulded parts, and the TG5 (Tolerance Group 5)
DIN 16742 is a standard that specifically deals with tool holders and their interfaces. Tool holders are essential components in machine tools, serving as the bridge between the machine and the cutting tool. They are critical in ensuring that the cutting tool is accurately positioned and securely held during the machining process. The standard covers various aspects, including dimensions, materials, and performance requirements for tool holders. din 16742 - tg5
Typical Ranges: 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. standard is a critical German guideline for determining
In the context of the standard’s tables, TG5 specifies a permissible deviation that is significantly tighter than what might be acceptable for a disposable item, yet achievable without exotic tooling or specialized environment controls. For example, on a nominal dimension of 100mm, the tolerance range in TG5 would be narrow enough to ensure good fitment with mating parts, but wide enough to account for the natural variability of the injection molding process. Cavities must be CNC-machined to IT7 grade (ISO
If you need the full text of the standard, I recommend checking the following sources:
| Feature | TG4 (Fine) | TG5 (Very Fine / Precision) | | :--- | :--- | :--- | | Relative stringency | Standard precision | High precision | | Mold cost | Moderate | High (requires hardened steel, 3+ slides) | | Typical application | Snap-fits, enclosures | Gears, bearings, optical housings | | Process window | Wide | Very narrow (requires dry resin, controlled environment) |