Hello guys,

I am a bit confused by these two - tolerance method or part to part variation, what is the difference when defining R&R with either? When do we use one when other?

We"ve got this audit coming up very soonand word "nightmare" slowly is creeping in here...

:cfingers:


Cheers

The one that you use depends on the gage use.

If the gage is used to inspect a part to specification, use P/T Ratio.

If the gage is used for process control such as SPC, or used for statistical studies such as a capability study, a DOE, a hypothesis test, etc. use %GRR (percent of total variation).

You can also search this forum for some more in-depth explanations that I have previously made for other posters.