Smooth Ring Gauge - ease of fit

We continually have an issue with inspectors subjectivity of how easily a smooth ring gauge (Go End) fits over a shaft OD for pass/fail. They have been trained to hold the shaft vertically and place the ring gauge over the top and it should fall down with gravity and if it doesn't, it fails. The part being inspected is made of polycarbonate and OD is 0.340" so the part is small. My take is that if I can push the gauge onto the shaft with relative ease, then it passes. The pushback I get is there's still subjectivity amongst various inspectors on what defines "relative ease". I have researched and found articles that state "with no force" and "without too much force".

Just wondering if anyone has experience on this issue. We are thinking about creating a fixture to hold the part in place and using a fixed weight to place on top of the gauge and if it pushes the gauge over the shaft, it passes, if not, it fails. This would take out the subjectivity, but then creates a lot of work to rationalize and validate what that weight should be.

Thanks much!

Michael

 

Gravity is the only standard I use. It eliminates the "greyness".

If you're looking at adding a weight to the process, you'll need your customer's buy-in or run the risk of different interpretation of PASS/FAIL.

 

Thanks much!

 

I met some fellows about thirty years ago who had a solution for that challenge ...

They modified the gauge until it fit the parts easily. I only worked there for a brief time.

 

Frankly, if your requiring that much precision is a ring gage the way to go?