Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

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

ASME or ISO 3

Status
Not open for further replies.

Troy442

Mechanical
Oct 7, 2008
12
0
0
US
Greetings,
I work at a USA based company. Currently we are making parts/drawings with SolidWorks to ASME 2009, 3rd angle projection, in inches. I did pass the GD&T 1994 exam for Technologist Level.

Like many companies many of our injection molds are made in China. We are also a 15 Billion dollar company for annual sales. So "we" continue to purchase smaller companies from around the globe.

You can see where this is going. The home office is use to inches and ASME. Other areas are Metric, 1st angle and ISO.

The current discussion is standardizing on:
Metric--ASME-- 1st or 3rd angle
Metric---ISO---1st angle
We will NOT be dual dimensioning

I am having a difficult time finding books written on ISO standards. Amazon has many selections geared to ASME but not ISO.

Thoughts? Opinions? What is in use today? IS Y14.5-2009 GD&T very similar to ISO? What are automotive (similar) companies using?

Thanks, Troy
 
Replies continue below

Recommended for you

Troy442,

Do a search on the ISO standards. To get a complete package of GD&T literature to the ISO standard costs quite a bit more than ASME Y14.5. You need to know what training is available, in the USA, in China, and everywhere else you have plants and vendors.

Congratulations on not dual dimensioning.

--
JHG
 
No company or country, ever, turned back to inches after going metric. So should you.

If your company can afford to buy other companies, it can afford to buy licence for using any ISO standards you need, on paper, or better yet on-line from here:
ISO standards today are going thru major revision, so textbooks you may be able to find will be, most likely, outdated.

No, Y14.5 is not very similar to ISO, but you can find a few surprises. If you seriously want to know what ISO is about philosophically, start with this book:
Automotive companies are using their own adopted versions of ISO

This should be enough to start a flame war :)

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future
 
Congratulation on going with single dim.. Since your company is buying many overseas companies you have a great advantage over other companies. Your company needs to go full metric and ISO. That is the preferred system as per US Government. No company in the world will go to inches. So use your overseas companies to help you along with ISO and metric. If you stick with imperial in the US you will create nothing but problems. Going with two systems is the worst thing you can do. Learn from others like the Auto Industry etc.. Some of your overseas companies could be operating with their own standards and not be fully ISO. So you may have to put some pressure on those companies to go ISO whenever possible.
Do not listen to people advocating dual system use! There are many out there saying that in today's world the calculator has made it a snap to convert. NOT SO!
 
My two cents is to definitely go metric.
As for the standard, I'm biased toward ASME. The automotive companies pretty much line up based on their country: US OEMs use ASME with metric and 3rd angle; Japanese use ISO with metric and 3rd angle; European mostly use ISO with metric and 1st angle. So you can see it's not a one-size-fits-all thing.
My reason for leaning toward ASME are several, including (I admit) simply having been raised on it. But from a practical point of view it's a single volume, not multiple standards with constantly overlapping revision dates! And it's less expensive. It's very much predominant here in the States, with lots of resources for training and textbooks.
However, ISO has an advantage in that it's more mathematically robust in some areas.
If you switch to ISO you will soon realize that the differences are a lot more numerous than you thought. The way the leaders point to a feature (normal to feature, not angled), the way extension lines come out from a corner, and the big one is the independency principle (rather than ASME's envelope principle).
So just do your homework and decide what's best for everyone.



John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems
 
You may also want to take a good look at what paper sizes your companies are using and try to find a common ground. ISO 216 {single aspect). The next thing when having companies in other countries is that you should agree on one system of how to write a date. Europe is mostly all DD/MM/YYYY, I believe Japan is YYYY/MM/DD. US is MM/DD/YYYY.
You won't believe how much of a problem this can be when communicating and doing business with other countries. Also make use of the 24 hour clock. It is best to lay out these rules so everybody understands when he is supposed to do what. Don't forget the US Military and the US Government works in metric and uses DD/MM/YYYY as well as the 24hr clock and they are all over the world. I guaranty you will get a lot of resistance from within your US company. Some people will resist any change for as they are still working. I went thru all this and we are still cleaning up some things that somebody refused to do. One thing - you must make sure you have the CEO on your side or nothing will get done.
 
jurgenwt said:
One thing - you must make sure you have the CEO on your side or nothing will get done.

Very true - at the end of the day you will do what your boss will tell you to do. The reform must start from the very top, otherwise it will never happen.

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 
One thing no one has mentioned is legacy drawings. I'm sure you have thousands of them. Are you going to redraw every one of them? We have a similar situation where we primarily use and prefer metric ISO 3rd angle drawings but we have purchased smaller companies or product lines done in inches and ASME. We have not redrawn and redimensioned old product lines. There is too much old documentation, tooling and gauging already in place. So we live in this world of simultaneously having both systems co-exist.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.
 
There is no need to redraw all the legacy drawings at once.

We had similar situation when switching the CAD systems. Old drawings were converted "as needed" following the revision process. The change column would say "redrawn in SolidWorks"

As long as drawing conforms to SOME standard and will be interpreted correctly, it still OK. If drawing doesn't follow ANY standard and never was, that's another problem (and not ISO's fault).

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 
First off thanks to all of you that took a few minutes from your busy day to respond to my post. I found good points in all of the comments.

We will not recreating "any" old files/documentation. Over the years we have gone from paper, AutoCADD, Pro/E (1991), to SolidWorks (2004) and have never made it a goal to recreate everything. There is occasionally that "new" project that has it's roots from old product line and that decision (Metric/Inch) will need to be made then.

I am going to purchase some of the ISO materials suggested to read over. Then our company can make an informed decision.

I enjoy the comment on date order. I have brought that up before and I get the strangest looks. I do like title blocks and rev blocks that say DD/MM/YYYY or MM/DD/YYYY versus DATE.

My guess is if we go Metric ASME it will be 3rd angle. Metric ISO will be 1st angle.

Thanks, Troy


 
Couple of more question form the Original Poster...

AMSE has Y14.5 and Y14.41. Does ISO have similar standards to Y14.41 for a Model Based Definition?

We use SolidWorks for CAD design and Innovemetric's PolyWorks for part inspection. I assume software packages are ISO/GPS capable? I know they are ASME/GD&T.

Thanks, Troy

 
Some historical trivia based on Genium materials:

The system of GD&T tolerancing is a British invention, and for this reason much of the early significant work in this field was done in the United Kingdom. In 1944 G. A. Gladman published “Drawing Office Practice in Relation to Interchangeable Components”. This paper, commonly referred to as "the Gladman paper," kindled the interest that led to new developments in tolerance theory in both the United Kingdom and the United States. The development of the International Standards Organization (ISO) interest in this subject has closely paralleled the British effort.
In 1945 the Gladman paper was presented at the War Engineering Annual Meeting of the SAE in Detroit; and, as previously mentioned, the presentation of this paper provoked widespread discussion regarding methods of tolerancing.
It is this concept which spurred the United States to adopt a specification system for Government and industrial requirements for dimensioning and tolerancing, defined by the American Society of Mechanical Engineers (ASME) and approved by the American National Standards Institute (ANSI).


"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 
I just noticed you complaining about absence of ISO references on Amazon.

Have you considered the following:

Book by Georg Henzold covering the latest (at the moment of publishing) ISO and ANSI/ASME standards and offers some insight into the world of GD&T/GPS:
Manual by Colin H. Simmons and Dennis E. Maguire based on BS8888 2011 and related ISO standards. Ideal for international use, it includes a guide to the fundamental differences between the relevant ISO and ASME standards:
Reference by Paul Green, Just like Simmons and Maguire Manual, the book shows exactly how to create technical drawings to a professional standard including drafting rules and not limited to dimensioning and tolerancing:
Book by the same author, has been created to simplify and codify the use and understanding of geometrical tolerancing. It is a complete, self-contained reference for daily use. Dedicated entirely to GD&T
Guide by Alex Krulikowski, one of the most complete ISO references for geometrical tolerancing on the market. One entire section is devoted to a quick comparison of ASME and ISO standards:
The only drawback of this book, as well as others, is that is based on 2004 vesion of ISO 1101 fundamental standard.
Also:
Handbook by Henrik S. Nielsen (this one takes the latest changes into consideration):
Although it is much cheaper to buy directly from ISO headquarters in Switzerland
Handbook by French agency AFNOR (I have no idea what’s inside, but it is about latest changes):
Do you still complain about lack of choices?


"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future
 
Thanks for the cool history and book suggestions. A few days ago I did buy the pdf version from Switzerland of the "ISO GPS Handbook." It is 378 pages and I am over 100 pages into it. Gets a little dry after a couple hours so I am breaking up the work day with it. I am going to read a bit on the Gladman Paper “Drawing Office Practice in Relation to Interchangeable Components” for the fun of it.

Thanks for the input, Troy
 
Status
Not open for further replies.
Back
Top