Calbrat
Automotive
- Mar 8, 2005
- 1
I am trying to certify 1/2 - 14 NPSF thread plug gage with a P.D. of .7700 - .7767. Can someone tell me which formula that needs to be used to check this thread size. I have looked into using the NPSM, NPSI and NPSL but there is something different about each one. The Machinist Handbook does not give a lot of information on this particular thread.