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Good question!
1&2) I think that GR&R's are useful when being done with tight tolerances. Unfortunately, no one else around here cares or seems to understand it. Doing a GR&R on every gauge listed on the control plan is a total waste of time and is primarily done to satisfy external auditors. The customers want their parts NOW and really don't even look at GR&R's, much less understand them.
An attribute GR&R is a total waste of time; in order to do it right you have to scrap a few parts. We run parts that have 30 plug gauges and 15 other gauges. Think of it, we have a plug gauge for this diameter: 10.5mm +/- .250. We'll use drills and reamers that are nominal size and do a CMM check 2-3 X per day. To do a proper attribute study I'd have to put in a smaller drill (and/or larger) than I'd normally use and then scrap off a few pieces. This is muda!
3) The getting smaller Big 3 do mandate it in order to keep themselves employed. Try getting a waiver from any of the SQE's for anything! Actually if they need the parts bad enough they'll waive gauge studies.
1&2) I think that GR&R's are useful when being done with tight tolerances. Unfortunately, no one else around here cares or seems to understand it. Doing a GR&R on every gauge listed on the control plan is a total waste of time and is primarily done to satisfy external auditors. The customers want their parts NOW and really don't even look at GR&R's, much less understand them.
An attribute GR&R is a total waste of time; in order to do it right you have to scrap a few parts. We run parts that have 30 plug gauges and 15 other gauges. Think of it, we have a plug gauge for this diameter: 10.5mm +/- .250. We'll use drills and reamers that are nominal size and do a CMM check 2-3 X per day. To do a proper attribute study I'd have to put in a smaller drill (and/or larger) than I'd normally use and then scrap off a few pieces. This is muda!
3) The getting smaller Big 3 do mandate it in order to keep themselves employed. Try getting a waiver from any of the SQE's for anything! Actually if they need the parts bad enough they'll waive gauge studies.