: Short undercut for external threads (used where space or material length is limited).

The exact dimensions of a DIN 76-A undercut depend entirely on the nominal diameter ( ) and the of the metric thread.

Tracking down a clean can feel like a scavenger hunt. Use the official preview for legal accuracy, or rely on standard engineering reference books for the charts. By adhering to these runout and undercut rules, you stop breaking threading tools and stop breaking shafts at the shoulder.

, you can view community-uploaded summaries and technical drafts on platforms like Course Hero dimensions (radius or width) for a particular thread size, such as Din 76-1 | PDF - Scribd Din 76-1 | PDF. Thread Relief Explained: Function, DIN 76 & Practical Use

An undercut matching DIN 76-A removes this imperfect thread area. It serves several crucial functions:

When looking for an official , it is important to note that the document is officially titled DIN 76-1 ("Tapping holes, thread run-outs and thread undercuts for ISO metric threads"). Tips for Sourcing the Document:

The English translation is prepared by the DIN language service; however, the standard notes that “in case of doubt, the German‑language original shall be considered authoritative.”