In my last column I listed some basic equipment requirements for the calibration of thread plug gages so I thought it would be helpful to give mating gages the same treatment.
Thread ring gages sold in North America are the adjustable type as standard compared with the rest of the world where they are solid or non-adjustable. Endless arguments over which is the better type to use for the typical threaded product will always be with us so I won’t go into great detail on that subject. However, the basic advantage of the solid thread ring is that it does not have a size adjustment that can be changed.