Howard Atkins said:
If there is a reason for the tolerances to be tightened then it should have been reflected in the
FMEA and the CP! This has nothing to do with using narrowed tolerances but the justification for them.
I don’t disagree with that at all, if we need the tighter tolerances to assure good product, it should be on the CP and FMEA. I’m still not convinced it’s a nonconformance, though.
The reason the WI’s have tighter tolerances is not that the process requires it, but to make sure our actuals really fall within the tolerance of the CP.
Say the CP requires a pressure gage to read between 10 and 30 psi. If the work instructions call this out, and the operator reads 8 psi, they’re probably going to think “good enough.” (I know, I know. What can you do?)
If the work instructions call out 15 to 25 psi, and the operator reads 8, they’ll call quality.
That’s the reason we had the tighter tolerances on the WI’s, and I had no idea it would be considered a nonconformance. The auditor’s reasoning was “The control plan is like your Bible, you have to follow it.”
My thought was “The Bible says don’t drink alcohol in excess, but if a family doesn’t believe in drinking alcohol at all, they are going to ****.” I kept my little mouth shut though.
I really don’t mind that we got the minor, as some of the WI specs just didn’t match. But I was surprised to hear from the auditor that we would have gotten it just for the too-tight specs.