Go, No Go gage tolerances

[rcontractor]

Hello,

As of this point, I found literature stating that the tolerance of a Go or No-Go gage must be no more than 1/10th of the total tolerance for that dimension. Is this a standard? Or should I also be accounting for the material used for the part, the gage, etc. Also, Class XX, X, Y and Z are for repetition of use? or just dependant on the type of tolerance you can expect to achieve....

In my case, the parts will probably be plastic and the gage will probably be stainless steel.

Thank you,

Ras

 

[jclough]

That 1/10 figure is not standard.

Go or No-Go gage tolerances vary depending on the size and class. The larger the gage the larger the tolerance.

The class is also an indication of tolerance.

Just what are you trying to do?

 

[rcontractor]

Jclough,

I am trying to determine the correct tolerances to machine Go/No Go gages made out of stainless steel to use on machined plastic and steel couplings for pipe.
For example, one gage will either go or not go over the OD of the machined pipe, and another gage will be machined to line up with lockwire slots as well as go in the ID of the pipe.

I hope this makes sense....dimensions are in the range of 2-4" on the ODs and IDs..

thank you

 

[jclough]

Go to the Glastonbury Gage web site. Click on the Tech Facts button then click on the Go/NoGo Gage Concepts link. This should give you a better understanding of the issues at hand. I'll still be willing to figure things out if you needit.I'm one of those who prefers to teach a man to fish. If you need the actual tolerances I can fax you a chart.

Let me know...


Jon

 

[rcontractor]

Hey Jon,

I read that site before I actually posted this topic, and the problem for me was that I already understood what a Go No Go gage(s) is, I just wasn't sure about the different tolerances, which wasn't there in a way I could understand anyways..

if you have a generic tolerance chart that I could use for different sizes/materials and fits, that would be much appreciated. I try not to post on here until I have a general idea what I'm dealing with, so dont' worry, I can bait my hook

drop me an email if you have a chance...thank you
rcontractor@slb.com

Ras