Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

Register Log in
  • Congratulations cowski on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

"S" in a circle. It's no longer needed?

Status
Not open for further replies.
cadman1964

cadman1964

Mechanical
Apr 22, 2009
135
I know the answer already i believe but i have some people here that doubt me, even knowing i have the ASME standard. According to ASME Y14.5M-1994 the "S" in a circle is no longer need, correct??. "S" use to mean "regardless of feature size"

I'm assuming the ASME didn't add this back in, correct???

Solid Edge V20
 
Replies continue below

Recommended for you

Sort by date Sort by votes
"S" was obsoleted in the 1994 standard and I did not find anything in the 2009 standard restoring it. "S" is gone!!!!

Dave D.
 
Upvote 0 Downvote
TY

Could anyone scan a copy of just the new MODIFYING SYMBOLS and post it? if it legal and all..:)

Solid Edge V20
 
Upvote 0 Downvote
Please ref to standard Y14.5 1994 Appendix D paragraph D3 page 215 and Fig.D-1 on page 216. RFS symbol is no longer required.

SeasonLee
 
Upvote 0 Downvote
LOL LOL, that's the deal. I did reference the page cause we have the whole standard. But still have some people who think they know the ASME standard back-wards and for-wards. One person had the gull to say "Maybe they forgot to put it in" Then i bring it to my boss's attention, he ones that thinks he knows it all, and he just gave me a bunch of crap and said he's not going to worry about it threw the drawing in the trash. O also he said "Well the customer (DELPHI) had it that way so it must be current"

Solid Edge V20
 
Upvote 0 Downvote
I wouldn't worry too much about it, given the grief you're seeing over it. The use of the symbol isn't going to result in an incorrect part.

"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]
 
Upvote 0 Downvote
I'm not going to worrie about any more after what just happen. I thought on the way back from lunch i'd stop by the new girl office who's doing all of our documentation and see if she understood my email. To say the least, i don't have a very good opion about her anymore. See also part of it is that they were drawing the "S" with a circle in our doc's and i was trying to convey to her that it's not needed. WHAT A JOKE around here at times

GO RED WINGS!!!!!!!!!!

Solid Edge V20
 
Upvote 0 Downvote
I feel your pain, and have learned to better pick my battles than I used to.

"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]
 
Upvote 0 Downvote
To use the symbol, you have to reference the 1982 standard on the drawing. In the 1994, it is only mentioned as something that is being killed off.

The reason that it is no longer necessary is that the 1994 standard makes RFS the assumed value, instadd of MMC. So, it is actually a good idea to NOT use it, as it would create confusion as to which standard you are using and whether no symbols means MMC or RFS. If MMC is even suggested as default and your drawing is done to 1994, then you can be really screwed.

I would suggest that it is not correct to use circle S, especially if you are now invoking 2009 on that print.

And, the S was not "forgotten" in 2009. That comment suggesting this is extremely off-the-cuff. Every statement change in the standard is debated endlessly before its inclusion or exclusion.

Matt Lorono
CAD Engineer/ECN Analyst
Silicon Valley, CA
Lorono's SolidWorks Resources
Co-moderator of Solidworks Yahoo! Group
and Mechnical.Engineering Yahoo! Group
 
Upvote 0 Downvote
Is there a note specifying which standard to interpret the drawing to? That will probably cover your butt if the situation arises regarding MMC that fcsuper mentions. It is no excuse to assume MMC if the drawing is to be interpreted to the '94 standard (for example) just because RFS is erroneously used.

"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]
 
Upvote 0 Downvote
TY ewh, i looked up one of the original drawings that has the customer Title box on it, it says ASME y14.5-1994

Solid Edge V20
 
Upvote 0 Downvote
I have to agree with fcsuper that misuse of the symbol can cause problems down the line, but you have to choose which battles to fight. It sounds like your work environment is similar to mine in that some things have to be put aside in order to tackle the bigger problems.

"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]
 
Upvote 0 Downvote
Oops, I meant to post "...in order to tackle the bigger opportunities."

"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]
 
Upvote 0 Downvote
The '94 standard had RFS as the implied condition if no modifier was present. Rule #2(b) allowed the use of the (S) modifier.

The '09 standard eliminated Rule #2(b), making it illegal to use the (S) modifier. I don't agree with this decision myself, but that's what the committee voted for.

Evan Janeshewski

Axymetrix Quality Engineering Inc.
 
Upvote 0 Downvote
There you go! It is legal to use it under the '94 standard. Thanks, Evan!

"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]
 
Upvote 0 Downvote
Evan

Rule #2a is an alternative practice of Rule #2. Rule #2a states that, for a tolerance of position, RFS may be specified in feature control frames if desired and applicable. In this case, the RFS symbol would be the symbol from the 1982 version of Y14.5, please ref to the attached examples of Rule #2 and Rule #2a ( from Alex Krulikowski GD&T Workbook ).

Would you please advise where I can find out Rule #2b.

SeasonLee
 
 http://files.engineering.com/getfile.aspx?folder=419374c2-01af-4cf7-8a50-28b3839f12c4&file=Rule#2a.pdf
Upvote 0 Downvote
SeasonLee,

I'll leave out the obvious Shakespeare joke here.

You're right, it's Rule #2a in the '94 standard. The section that it's in is 2.8(b) on page 28.

I had looked it up in the Former Practices appendix in the '09 standard, which says that Rule #2(b) has been eliminated. Looks like there's another typo in '09 to report.

Evan Janeshewski

Axymetrix Quality Engineering Inc.
 
Upvote 0 Downvote
ctopher, not at work but, is that from the 2009 standard??

Once back to work tomorrow i'll have to get the ASME standard out and look up #2a

If true, thinking of not saying anything....[ponder]

Solid Edge V20
 
Upvote 0 Downvote
Status
Not open for further replies.

Similar threads

penjo1
  • Locked
  • Question
Position and it's Required Datums
Replies
3
Views
488
3DDave
3DDave
RPars
  • Locked
  • Question
Applying Datums to "Stock" Features 1
Replies
2
Views
286
RPars
RPars
monkey_brain_ideas
  • Question
Pedigree in a Part Number? 1
Replies
7
Views
4K
Wuzhee
Wuzhee
F
  • Question
Profile tolerance unless otherwise specified - WRT Datums vs no datums 1
2
Replies
32
Views
8K
Burunduk
Burunduk
Burunduk
  • Locked
  • Question
No Y14.5 version referencing Y14.5.1-2019. And, what is the "single solution"? 3
2
Replies
21
Views
1K
SeasonLee
SeasonLee

Part and Inventory Search

Sponsor

Back
Top Bottom