Non-uniform profile tolerance

[prdave00]

My company is still operating under ASME Y14.5-1994, but I'd like to take advantage of the non-uniform profile tolerance concept in 2009. Any ideas on a general note that could be added to the general profile tolerance annotation to communicate this concept without having to transition to the 2009 edition?

 

[ewh]

Add a note stating that profile tolerances are per ASME 14.41-2003?

"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]

 

[KENAT]

Or even better to ASME Y14.5-2009.;-)

Posting guidelines faq731-376

http://eng-tips.com/market.cfm?

(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​

 

[prdave00]

ewh: Can you oblige me with the definition in that standard? I don't have immediate access to that Y14 standard. In your opinion, is it acceptable to reference that standard if a company hasn't adopted digital, solid model tolerancing?

 

[prdave00]

KENAT: I would love to transition over to the 2009 revision of Y14.5, but there is push back from quality assurance and engineers only familiar with earlier versions of Y14.5. I did it successfully once, but I don't think I can do it twice.

I think I'd have an easier/better chance of selling my the addition to my annotation that I am seeking to QA and engineering as an extension of principal to Y14.5M-1994.

 

[pmarc]

prdave00,
How does the general profile tolerance annotation look like at the moment?

 

[Belanger]

You should make the note so confusing that your colleagues will insist on switching to the 2009 standard.

John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems

 

[KENAT]

ewh's point - or at least mine - was not to transfer the entire drawing over, just that 1 tolerance.

Posting guidelines faq731-376

http://eng-tips.com/market.cfm?

(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​

 

[ewh]

It is the same definition as that in the Y14.5-2009. I have seen (and used) a note to allow use of the newer symbology without invoking the entire standard ("PROFILE TOLERANCE TO BE INTERPRETED PER ASME Y14.41-2003"). The reference to Y14.41 was so as not to confuse the issue for companies not yet using Y14.5-2009. I doubt it matters very much which standard you refer to, as long as you refer to one with the interpretation you want to use.

"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]

 

[prdave00]

All: Thanks for your feedback. I've now attached the problem I'm trying to solve - see the two circled areas in the bottom half of the presentation. I want to communicate that the transitions between the surfaces controlled by profile and the surfaces controlled by the position & size should be smooth. In reality the part could be stepped and still be functional based on a gut feel, but I don't necessarily want there to be a sharp and potential stress riser (and it would look funny). I guess this is a bit different than the NON-UNIFORM concept in 2009, but I'd say it's a similar spirit.

pmarc: Please see attached for what the general note says currently.

Belanger: My colleagues are already confused enough on GD&T in general, so added confusion may not help. Instead of understanding, I think they'd just pick on the fact that we don't subscribe to the 2009 revision yet and no one is technically trained to it. 1994 has already been grandfathered in, so no one has been technically trained to that either, but pointing that out won't help my cause! Argh.

 

[pmarc]

prdave00,

Two things:
1. Seeing how your general notes look like, I would suggest:
- changing note #1 a little bit to something like: "UNLESS OTHERWISE STATED GD&T PER ASME Y14.5M-1994";
- and like Kenat said, mark somehow that this particular tolerance should be interpreted per Y14.5-2009.

If you do not feel comfortable with referring to 2009 edition on the print you could try to...:
- remove phrase "NON-UNIFORM" from profile FCF, put remark "SEE NOTE #3" instead and write in general notes that: "3. PROFILE OF SURFACE TOLERANCE ZONE AS DEFINED BY BASIC DIMENSIONS" or similar.

2. Regardless of how you wil do it, I think profile of surface with non-uniform tolerance zone can work here only if there is no datum reference within non-uniform profile FCF. Presence of any datum reference will cause that the zone for profile of surface tolerance will be fixed with relation to that datum. While nominally tangent surface of .063 cylinder controlled by .002 positional tolerance can float up and down within limits allowed by positional tolerance, the blended surface must stay within fixed tolerance zone, so theoretically there is still a possibility of an abruption in the transition area.

Side note: if the single radius was tangent on its both sides I would recommend using typical directly toleranced radius dimension which as a matter of fact creates non-uniform tolerance zone, quite similar to the one you probably want to define by profile callout (see fig. 2-22 of Y14.5-2009).

 

[ewh]

pmarc,
If the 2009 issue isn't desired, wouldn't my sugestion of Y14.41 be valid? I used such a note before Y14.5-2009 was issued without any problems.

"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]

 

[pmarc]

ewh,
Could you tell me exactly which paragraph/figure of Y14.41-2003 says something about non-uniform profile of surface tolerance zone? I am having serious troubles in finding anything:-(

 

[ewh]

[¶] 10.2.3(e), pg 41
&
fig. 10-19, pg 70


"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]

 

[pmarc]

ewh,
Are you thinking about unequally disposed profile tolerance zone? This is not the same as non-uniform profile tolerance zone.

 

[Belanger]

When I first saw this thread, I thought it was the unequally disposed thing. Then I had to stop and think about non-uniform!

John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems

 

[pmarc]

J-P,
If the thing was about unequally disposed profile tolerance zone, I don't think OP would have any issues, because this concept is pretty well covered in 1994 edition.

 

[Belanger]

Right, pmarc. I was just commenting on your comment to ewh.

John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems

 

[ewh]

Yep, caught me. Thanks for the clarification.

"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]

 

[prdave00]

Thanks for all the suggestions. Although it's possible that the finished part could look like I drew it where the surfaces aren't blended, I've convinced myself that it's probably not probable given the way our supplier intends to manufacture it. If this bites me in the rear end, I'll repost to offer up a life's lesson.