The ISO metric screw threads are the world-wide most commonly used type of general-purpose screw thread. They were one of the first international standards agreed when the International Organization for Standardization was set up in 1947.
The "M" designation for metric screws indicates the nominal outer diameter of the screw, in millimeters e.g., an M12 screw has a nominal outer diameter of 12 millimeters.
4H and 6G taps can be supplied upon request. 6G taps are Oversize. Please refer to the Au "G" values table below.
For the special tolerance "7G", an oversize of approx. 2 x Au "G" has been taken into account.
Tolerance Chart - Metric Coarse / Fine
Tolerance Chart - Oversize 6G Taps
Au "G" Values for Oversize Taps "6G Taps"
Technical Support Blog
At Next Generation Tool we often run into many of the same technical questions from different customers. This section should answer many of your most common questions.
We set up this special blog for the most commonly asked questions and machinist data tables for your easy reference.
If you've got a question that's not answered here, then just send us a quick note via email or reach one of us on our CONTACTS page here on the website.
Our technical section is written by several different people. Sometimes, it's from our team here at Next Generation Tooling & at other times it's by one of the innovative manufacturer's we represent in California and Nevada.