S
Sam
Zeno,
Did you get any response from the website I referred you top?
Did you get any response from the website I referred you top?
Flatness / Straightness / Bow specification
- Thread starter Proud Liberal
- Start date
B
Bill Ryan - 2007
The North American Die Casting Association (NADCA.com) also addresses this type of specification for castings. They should be able to give you an "authoritative" response (I'm not sure they would be any more responsive than ANSI, though).
Good luck and let us know if you get any closure.
Bill
Good luck and let us know if you get any closure.
Bill
Proud Liberal
Quite Involved in Discussions
I tried checking out the die casting web site and couldn't find any information (at least in the non-member available areas).
As far as replies from other forums .........
the CMMTalk forum reply was:
"Ed Morse
Posted - 11/6/2002 1:39:34 PM
-------------------------
Jeff,
It appears that you know the answer and are just looking for some backup. Here it is. Your customer's interpretation of the standard is incorrect.
(for now we'll live with whatever assumptions you and the customer make about the arc/foot measured being representative of the entire part length -- I don't think that is the issue in question)
The "unfortunate" example in Y14.5M is actually very good: it shows you that the total straightness is NOT simply the per-unit value times the length.
There is nothing wrong with the Geometrics example, except that this condition is not explicitly stated as it is in the standard. One approach you might use in discussing with your customer is to say "If the upper (0.020") part of the composite straightness tolerance wasn't necessary, IT WOULDN'T BE THERE."
Hope this helps,
-Ed."
The GD&T forum replies were:
"From: Dave Schenken [email protected]
Date: 11/6/02
Time: 8:52:51 PM
Remote Name: 63.208.47.22
Comments
Check out the Aluminum Association handbook - AA1, which was adopted as ANSI H35.1. It describes exactly the type of problems you have - just for metal.
It provides explicit methods and interpretations."
"From: Dave Schenken [email protected]
Date: 11/6/02
Time: 10:03:38 PM
Remote Name: 63.208.47.22
Comments
Sorry - tolerances are in H35.2. "Dimensional Tolerances for Aluminum Mill Products, 2000"
H35.1 is alloys.
Readily found on internet."
I checked out H35.2 and found it to be $60. Hardly worth it for one or two paragraphs of clarification.
As far as replies from other forums .........
the CMMTalk forum reply was:
"Ed Morse
Posted - 11/6/2002 1:39:34 PM
-------------------------
Jeff,
It appears that you know the answer and are just looking for some backup. Here it is. Your customer's interpretation of the standard is incorrect.
(for now we'll live with whatever assumptions you and the customer make about the arc/foot measured being representative of the entire part length -- I don't think that is the issue in question)
The "unfortunate" example in Y14.5M is actually very good: it shows you that the total straightness is NOT simply the per-unit value times the length.
There is nothing wrong with the Geometrics example, except that this condition is not explicitly stated as it is in the standard. One approach you might use in discussing with your customer is to say "If the upper (0.020") part of the composite straightness tolerance wasn't necessary, IT WOULDN'T BE THERE."
Hope this helps,
-Ed."
The GD&T forum replies were:
"From: Dave Schenken [email protected]
Date: 11/6/02
Time: 8:52:51 PM
Remote Name: 63.208.47.22
Comments
Check out the Aluminum Association handbook - AA1, which was adopted as ANSI H35.1. It describes exactly the type of problems you have - just for metal.
It provides explicit methods and interpretations."
"From: Dave Schenken [email protected]
Date: 11/6/02
Time: 10:03:38 PM
Remote Name: 63.208.47.22
Comments
Sorry - tolerances are in H35.2. "Dimensional Tolerances for Aluminum Mill Products, 2000"
H35.1 is alloys.
Readily found on internet."
I checked out H35.2 and found it to be $60. Hardly worth it for one or two paragraphs of clarification.
