Would this part be out of specs ?
Would this part be out of specs ?
(OP)
This is a hypothetical example, but it is applicable to a lot of my company's parts. I would like to get a better clarification on this.
We use ASME Y14.9-2009. Attached is the drawing to give a better visual representation.
Basically, if I have a plate with a pocket that calls out .040 +/-.002, I would assume that the flatness on the bottom of the pocket to be less than or equal to .004. I know this isn't exactly the envelope rule (rule #1), but it is very similar.
However, the actual part is bent once it is un-clamped from the machine. The local depth of the pocket is still within tolerance .040 +/-.002, but the total height is .092 (just hypothetical) due to the deflection. Thus, this part is not within specs.
1. Is it correct to reject this part?
2. Is it correct to assume that the bottom of the pocket has to be within .004 flat based on the limit of size of the .040+/-.002 ?
All helps are appreciated.
Thanks.
We use ASME Y14.9-2009. Attached is the drawing to give a better visual representation.
Basically, if I have a plate with a pocket that calls out .040 +/-.002, I would assume that the flatness on the bottom of the pocket to be less than or equal to .004. I know this isn't exactly the envelope rule (rule #1), but it is very similar.
However, the actual part is bent once it is un-clamped from the machine. The local depth of the pocket is still within tolerance .040 +/-.002, but the total height is .092 (just hypothetical) due to the deflection. Thus, this part is not within specs.
1. Is it correct to reject this part?
2. Is it correct to assume that the bottom of the pocket has to be within .004 flat based on the limit of size of the .040+/-.002 ?
All helps are appreciated.
Thanks.





RE: Would this part be out of specs ?
So far your specs are ambiguous, and their interpretation may vary.
To define your pocket better you have to apply controls like Parallelism, Flatness, etc. in accordance with ASME Y14.9-2009
"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future
RE: Would this part be out of specs ?
John Acosta, GDTP Senior Level
Manufacturing Engineering Tech
SSG, U.S. Army
Taji, Iraq OIF II
RE: Would this part be out of specs ?
John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems
RE: Would this part be out of specs ?
@CH: I agree that the pocket needs to define better like you stated. However, if it is just defined as in drawing, can we come to a conclusion? Or like you said, the drawing is too ambiguous that no conclusion can be drawn.
For hypothetical purpose, can the pocket depth even be checked properly?
Thanks for all the helps.
RE: Would this part be out of specs ?
As soon as you ask yourself "from which point to which point?" you'll realize that 2 people will have 3 opinions about possible conclusion.
So, I'm afraid not.
"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future