In the world of high-precision manufacturing, DIN 16742 is the law of the land for plastic molded parts, and TG5 is its elite "Accurate Production" standard. This is a story of a part that refused to fit—and the engineer who had to fix it. The Precision Paradox Elias stared at the 3D model of the " Nexus Connector
Use TG5 for general-purpose plastic parts where fit is important but doesn't require extreme "watchmaker" precision Higher Groups:
Standard high-quality injection molding; high dimensional stability din 16742 - tg5
TOLERANCES: DIN 16742 – TG5
Draft angles: 1.0° per side unless noted
All dimensions in mm; burrs max. 0.2 mm
Unlike metal machining tolerances (which are often absolute), TG5 tolerances are relative to the nominal dimension. In the world of high-precision manufacturing, DIN 16742
DIN 16742 is the German industrial standard used to define manufacturing tolerances and acceptance conditions for plastic moulded parts. It replaced the older DIN 16901 and is often used alongside or as a reference for the international standard ISO 20457. Tolerance Group 5 (TG5) Overview
Do not default to TG5. Specify it only for: It replaced the older DIN 16901 and is
Dimensional Limits: In TG5, the allowable deviation increases as the dimension of the part grows. For example, a 10mm feature might have a tolerance of ±0.08plus or minus 0.08 mm, whereas a 100mm feature might allow ±0.22plus or minus 0.22
: It is often specified for "hard" plastic components or multi-component parts where a more accurate fit is needed (e.g., snap-fits or bearing housings). Cost vs. Accuracy