Since I am dyslexic, I will answer the questions backwards. First the R&R. The MSA manual does not provide any “Hard and Fast” rules about GR&R acceptance criteria. However, they do provide “guidelines” for acceptance. (which most customers adopt as gospel) The guidelines are as follows:
Under 10% - measurement system is acceptable
10% - 30% - may be acceptable based upon importance of application, cost of gage, cost of repair
Over 30% - measurement system needs improvement.
You really need to look at the characteristic’s importance, tolerance, gaging technique and technology availability, cost, customer’s needs and expectations… ect to assist you in making these determinations. For example, if you have to develop some exotic gaging utilizing new technology at a very high cost and you have demonstrated that 30% is as good as it is going to get, a customer will most likely accept this. However, if you are measuring a bore and getting 30% error I guarantee you will feel some resistance and hesitation from the customer as the technology is there at reasonable cost to measure this repetitively.
You have to decide in conjunction with your customer what is practical for your business needs. But don’t go to your customer with out plenty of ammo to support your argument.
Secondly, the calibration examples. Drop me an e-mail and tell me your needs. Provide me with a fax, and I see what I can muster up for you.
