A reader emailed me after reading some of my rants on thread ring gages dealing with the problems that come up in their use and calibration. But he added another dimension to the problem since he is in the calibration business: How do the Europeans deal with their solid thread ring gages?
The term ‘proficiency testing’ is one that every accredited calibration laboratory is quite familiar with. In basic terms it refers to a method of evaluating how well a laboratory is doing a particular calibration with respect to its claimed measurement uncertainty and how it fares with other participants.
If you’re having problems with thread measurements but the answers you’re getting from your usual sources aren’t solving them, it’s natural that you would try and get some unbiased advice from a specialist.