%GRR <10% not possible. How to get approval by auditor?

[Chn01]

Gage R&R study according MSA 4rd Edition < 10% - That’s nice but often not practicable but ALWAYS required by auditors!

We use CMMs at shop-floor which are very accurate but for some characteristics there is no way to achieve <10%. In this case we accept internal between 10% and 20% but not the auditor.
In this case, the auditors require customer approval. Usually we get from the customer the approval verbal but not signed by a piece of paper.

Does somebody has an idea / solution how to get auditors acceptance without begging customer for signature?

Regards, Christian

 

[Ninja]

Optimal: Have the customer accept in writing, signed.
Near Optimal: Have the customer accept by email...that is "in writing".
maybe passable: document the verbal phone call with time, date and who said it.

From another aspect...if you can't get <10...perhaps you should still be looking at your test method to see how to optimize it.

HTH

 

[Sebastian]

I am not a CMM specialist, but for me it looks like unreliable measuring procedure. Improperly stabilized part during measurement, too small base planes, etc. These are basic mistakes and I do not believe persons at your plant made it, but better check it.
It is not question of auditor, it is question of unreliable measuring system, who in most cases should be best one. We have stamped parts and we do not use cmm for measuring positions on a daily basis.

 

[JJ_FDA]

Bake the approval into the specification documents or contract?

 

[Miner]

The MSA manual, 4th edition, page 78, states 10 percent to 30 percent "Should be approved by the customer". There is always a discussion and misunderstanding over the use of should vs. shall. See article.

In your situation, I think documenting a good faith effort to advise the customer and obtain the approval is sufficient.

The manual also states "Decision should be based upon, for example, importance of application measurement, cost of measurement device, cost of rework or repair". This provides another opportunity for you to document the justification for accepting the higher GRR.

 

[Golfman25]

Yep, this old problem again.

Your first try should be to look at your ppap submission. The gage r&r should be in there. Since the ppap was approved, therefore the gage r&r was approved. Used to work but these days not so much -- god forbid we expect customers to review our submission prior to approval.

Unfortunately auto auditors these days want detailed acts of congress for approval. Anything less and you'll have problems. So your best bet is to get a written approval from your customer using the audit finding as leverage for a response. Like anything with a hard number, you're stuck between meeting the number and actually using thought and reason. Good luck.

 

[Proud Liberal]

Your signed PSW should be good enough.

 

[Golfman25]

Your signed PSW should be good enough.

Unfortunately that's not true any longer. We went for years with alleged defects being "approved" by our customers via the signed PSW. Then one day all that stopped. Even an approved PSW doesn't get you out of the "requirement." We are told approvals need to be specific and documented. Your mileage may vary.

 

[Chn01]

Optimal: Have the customer accept in writing, signed.
Near Optimal: Have the customer accept by email...that is "in writing".
maybe passable: document the verbal phone call with time, date and who said it.

From another aspect...if you can't get <10...perhaps you should still be looking at your test method to see how to optimize it.

HTH

the auditor only accept in writing and sigened but in real life you don't get it. I would be very interested if somebody has such signed document from the customer?

Method optimizaiton has been done for many years. Sometimes there are limitation.

 

[Ninja]

Gage R&R is part of the full PPAP submission...the full PPAP submission is signed off and approved...thus I have a signed approval...

but not a separate signed document saying "We, the customer, accept a GRR between 10 and 20"

Haven't had any issue so far.