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Shop Pet Peeves

Inspectors writing up a NCR on a part for a fractional dimension being out of tolerance by 0.001". Tolerance is +/-1/32". Checking it with a pair of dial calipers. They don't know how to measure with a Starrett 4R ruler and say it is okay. Or use a tape measure to check a part that is 6 foot long with a +/-1/8" tolerance.
Counter point:
The part has a +/- 1/32" tolerance and they still couldn't hit it?
If it doesn't matter to miss the tolerance without further thought then the tolerance is wrong.
I don't want my quality inspectors to decide if a non-conformant part is ok to use. I want them to report it to engineering, who has the option of saying "Sure, use it" after 5 seconds of thought.
 
Counter point:
The part has a +/- 1/32" tolerance and they still couldn't hit it?
If it doesn't matter to miss the tolerance without further thought then the tolerance is wrong.
I don't want my quality inspectors to decide if a non-conformant part is ok to use. I want them to report it to engineering, who has the option of saying "Sure, use it" after 5 seconds of thought.
I sort of agree but sometimes many things could be a very wide tolerance, but not all at once.

IMO it's better to make a tolerance of +-0.005" on the height of a punch and a die each, than to give a tolerance of +-0.01" for height of each part and have a separate callout saying the combined height of the punch and die need to be +-0.01". It gets even weirder when the pinch point of the punch and die could move up or down by 0.5" or more, but the closed height needs to be accurate.
 
My biggest shop peeves are when I need to use a machine and someone left it full of chips and when someone left the tool and collet in the machine. We share machines ars we go (2 people know how to use them with maybe a dozen total with access) and have 2 BPs and a crappy lathe along with some other goodies. People apparently cannot be bothered to take a cutter out of a machine or sweep aluminum off the floor so we don't fall on our asses moving about the shop.


At my personal shop the floor is cleaned every time I finish a job or once a day, whichever is more convenient. I never leave tooling in machine unless I have to leave with a part in progress in the vice or chuck. The lathe is cleaned every couple jobs, or once a day, depending on amount of chips. I'd rather not fall on my ass by a running machine and I can't stand messes. I'm also anal retentive.
 
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Not exactly a "shop" peeve, but there have been two closely-related questions -- almost always from customers, but every once in a while from co-worker engineers -- that drove me up the wall: "What is the accuracy of your measurement?", and its cousin, "What is the error of your measurement?"

To the best of my recollection, no one asking either of those questions has accepted the best answer I've been able to give, "I can't tell you the accuracy (or error) of our measurements, but the three-sigma uncertainty is . . . ".

Common somewhat-related questions that have irritated me have been "How come all of your True-Position Errors are positive?" and, when dealing with the spatial relationship between two functionally-interrelated components, "The True-Position errors are all of the same sign, so to some extent they compensate."
 








 
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