Re: Gauge R&R studies - How often do you have to repeat a gage R&R study?
Ever read through a thread as an outsider and see clearly that people are talking about two different topics? This seems to be the case here (though Bob and Bev are trying well to point this out too).
Gage R&R is a test to see if a measurement method (Gage and use of that gage) is appropriate for measuring a particular feature/characteristic.
It either is appropriate or is not appropriate...period.
Three years of waiting will not chage its appropriateness. Heavy use will not change its appropriateness.
A new customer will not change its appropriateness.
Based on this alone, Gage R&R is a one time proof.
When operators change, it may be worthwhile to verify that the new ones are using the same method. This does not require Gage R&R, though you may choose to use that tool.
When a gage is used heavily and may drift, it may be worthwhile to verify that the gage is still accurate and repeatable. This does not require Gage R&R, though you may choose to use that tool.
Bottom line is that Gage R&R does not have to be run again...the test method is appropriate for that which is being tested.
You may choose to run it again for some other purpose...but there is no need to check for appropriateness again.