To help you get the exact data you need, could you specify if you are working with ? If you have a specific thread size in mind (like M8 or M12 ), let me know and I can provide its precise geometric tolerances. Share public link
If you are currently setting up a manufacturing print or a CNC program, let me know:
(coarse and fine pitch) according to DIN 13-1 and DIN ISO 261. pipe threads conforming to ISO 228 Part 1. Deals with trapezoidal, buttress, and knuckle threads , as well as other coarse pitch threads. Why It Matters Notch Effect Reduction:
A sharp corner creates a high-stress concentration point, which can lead to fatigue failure. DIN 76-A specifies a precise radius ( ) at the corners of the groove to distribute stress evenly. Reference Dimension Table for DIN 76-A
If you require the official, unedited engineering document for your compliance records, you can obtain it through official standardization bodies. Where to Download Official Copies din 76-a pdf
In modern CAD environments (such as SolidWorks, Autodesk Inventor, or PTC Creo), you do not need to manually model the intricate geometries of the undercut unless required for specific CAM simulations.
A standard DIN 76-A PDF blueprint contains specific tables detailing the following parameters:
The dimensions of a DIN 76-A undercut depend entirely on the thread pitch (
The letter specifically designates the type of thread undercut (Gewindefreistich) intended for external threads (bolts and screws). Key Differences Within the Standard: DIN 76-A : Standard undercut for external metric threads. To help you get the exact data you
Understanding DIN 76-A: Dimensions, Applications, and Specifications for Thread Undercuts
DIN 76-1 is the standard established by the Deutsches Institut für Normung (German Institute for Standardization) that dictates the dimensions for for ISO metric threads.
Sharp corners in mechanical parts act as "stress risers" where cracks can easily form under tension or vibration. The controlled transition radius (
The standard is divided into two main parts: pipe threads conforming to ISO 228 Part 1
) of the metric thread, rather than just the major diameter ( Key Geometric Parameters
Standard thread undercut for external (male) threads.
The Ultimate Guide to DIN 76-1: Thread Runouts and Undercuts (Free PDF Resources Explained)