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Maybe its me..but..

doctordremel

New member
I've been doing this, designing, drafting wild-assed weirdo it might work ideaing now for 13 years and have worked at 7 different firms ALL of whom are SO insistent that and their notes read so on the dwg formats that this drawing conforms to ASME Y14 whatever or MIL this or that and not one of them have had a copy of the relevant standard anywhere I could find it and each supervisor or checker had his own 'take' on where and how dims notes callouts and tolerance should be. OS each couple of years I have to find out the tribal Wisdom of how we do it here.



And don't get me started on ISO whatever Certified ;-)
 

dr_gallup

Moderator
We created an SOP that explicitly states each and every ISO or ANSI drawing convention that we use in the creation and interpretation of our drawings and reference it on every drawing. We also have a controlled copy of each of the standards. To my knowledge, Purchasing has never provided a vendor with a copy of our SOP and I can only recall one vendor ever asking me for it!



I worked in France for 2 years for a large diversified corporation and asked them what standard they used for their drawings and they all said ISO. Well, there are about 10,000 ISO standards that pertain to technical drawings and you can't conform to all of them since many are contradictory.



I asked them if they used ISO 8015: Fundamental Tolerancing Principal and they all said yes. They I asked them to explain how they would interpert a dimension and they all contradicted ISO 8015. Then I asked how they knew what a dimension meant and they said We all go to the same schools so we all learn the same way. Yeah right. Even the head of their CAD/drafting department could not show me any document that explained how to interpret their drawings.
 

donha

New member
The bottom line is can the information (drawing) convey, without any misinterpretation, the information you are attempting to convey? Many times it is the designer who is lacking in Y14.5m, GD&T, product knowledge, software skills and part creation processes.



The company I work for saw many years ago, that without the company having it's own CAD/Drafting standards, you simply could not have consistency between drawings. The person who put together the standards did an excellent job. Pretty much everything on a drawing was covered, including text height, note placement and dimensioning standards.



We presently have a CAD Standards committee who oversea the standards are kept up to date. All Pro/E stations worldwide use basically the same config.pro and drawing setup.dtl. Globally we are not completely on the same plane, but working at it.



I used to contract, so I understand moving from one company to another and re-learning the drafting procedures. I think the greatest shock was drafting in 1st Angle Projection.
 

dougr

New member
I think the greatest shock was drafting in 1st Angle Projection.



Mine was 3rd Angle and working in inches..
 

swcalvert

New member
Dr_gallup & Don, is there any way I could see either of your drawing standards? I'm in the process of re-writing ours and want to make a good impression by using (in part) a tried and true standard.



I'm not really sure I want to get into text height and note placement, mainly because I'm witting this to include PCB standards also.



Steve C
 

doctordremel

New member
I guess its NOT me after all. But I can't help but thinking that the real failure in the whole ASME standards process is where everything is said and done that each company STILL goes and writes their own standard.



Whenever I get in a bind I always go back to my college textbook Principles of Engineering Graphics to look up a line width or whatever. I was a board draftsman (before we became PC and said drafters ;-) in 1970's and learned good format and style.
 

swcalvert

New member
I don't think it's enough to say you're compliant with Y14.5M, Y14.1, Y14.41, Y1.1 or anything else. Most companies want a written standard that would, in turn, reference other standards and they want their own touch applied to it.



Steve C
 

swcalvert

New member
Oh, and another thing. I don't believe that any of these specs tell you what color your notes should be or what layers you should be using. This is what I'm after, just a simple start point for Pro/E CAD standards that I might put into a drawing standard for our company.



Steve C
 

dr_gallup

Moderator
swcalvert:



Email me at dgallup at smpcorp.com and I'll send you a PDF file of our drawing standard. It only covers how to read our drawings, not things like layer conventions. We do have an SOP on using Pro/E but it doesn't cover much about linestyles or layers either because once you set up Pro/E it's pretty much all automatic, unlike AutoMAD.



It is vital to have a clearly defined standard because there is so much variation in localized interpretation around the world. Just look at how most US firms use the number of decimal places to control default tolerances. No one working with metric dimensions does that. Also, the envelope principal of perfect form at MMC is not assumed if you use ISO 8015!



We've gone beyond ISO 9000 and are now TS 16949 certified. Fortunately it did not have any impact on our drawing practices.
 

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