Question on 'Class of Fit' - Gage Pin Clearance

[Ron Rompen]

Our customer has just contacted us regarding a proposed print change - they have asked to add a note 'Gage Pin MUST Pass freely (Drop) thru the center I.D. of the gear' and would like our approval on this (as soon as possible, of course).

I am (relatively) aware of the the ANSI standard for Class of Fit, but this isn't referencing anything like that - just a very ambiguous standard.

Does anyone know of any DOCUMENTED analysis which shows how much clearance is required for a gage pin to 'drop' through a hole.

If the dimensions matter, the hole diameter is ~0.500" and the overall height of the hole is ~1.500"

Thanks in advance.

 

[howste]

Here's a link to an ANSI tolerance calculator:
http://www.amesweb.info/FitTolerance/FitToleranceImperial.aspx

Now you need to interpret what class of fit the customer means when they say "Pass freely (Drop) thru the center I.D." I'm guessing maybe RC7 Free Running fit? You may also have to adjust for the fact that the gage pin will have a tighter tolerance than shown in the calculator.

 

[Ron Rompen]

Here's a link to an ANSI tolerance calculator:
http://www.amesweb.info/FitTolerance/FitToleranceImperial.aspx

Now you need to interpret what class of fit the customer means when they say "Pass freely (Drop) thru the center I.D." I'm guessing maybe RC7 Free Running fit? You may also have to adjust for the fact that the gage pin will have a tighter tolerance than shown in the calculator.

Thanks for the link, Howste. I agree, the interpretation of what 'pass freely thru...' is essential. Unfortunately, they have not been able to clarify it any further - making it extremely difficult for us to assess the feasibility of their request.