Diameter Measurement advice requested

[optomist1]

Great thread, as I am re acclimating myself to the GD&T arena. Re: Grok in general, Grok's responses have consistently (not on average been better than Chat GPT, Gemini, etc. A bit more (I have not read all the great input above), if one uses a go-no go plug, average is irrelevant?

Cheers
optomist1

 

[Bev D]

Using a go, no-go gage would result in either the min or max diameter controlling acceptance. BUT the function drives the dimensioning and therefor the gauging. A simple example is a ‘pipe’. If the pipe is for air or fluid flow the average or the min diameter may be sufficient. But if it is to hold a press fit bearing then circularity and full diameter matter.