ISO GTOL (GPS) Stds 2

[dlloydks]

Are there other companies out there that have switched from Y14.5 to the ISO GTOl stds? If so, how did you manage to get people to switch their thinking from Envelope Requirement to Independency Principle?

Also, I have been using the term "basic" for 40 years and am having a hard time using "theoretically exact dimension". What term do you use for a TED?

 

[pmarc]

Well, not going too much into details, there is ISO modifier that would bring Independency Principle back into play for features that do not need to be controlled by print-default Envelope Principle.

It is LP abbreviation enclosed within elongated circle. It stands for two-point measurement, so makes Independency Principle in charge again for particular feature of size if any other default principle governs the print (like Envelope Rule in your case). It was introduced in 2010 by ISO 14405-1 standard which specified tons of other modifiers that could be also used in conjuction with size dimension.

But in my opinion you do not really need this. I guess general notes on a print like below would work sufficiently.
- UNLESS OTHERWISE SPECIFIED, ENVELOPE PRINCIPLE IS INVOKED;
- FOR DIMENSIONS MARKED <any symbol> ENVELOPE PRINCIPLE DOES NOT APPLY.

 

[CheckerHater]

To fscuper:

I am sorry if all you could extract from my posts was "dissing". You went on the limb defending Russians; that justifies a pat-down. I expected person who called Metric system un-American activity to be more thick-skinned. But I promise in the future to threat you with respect you deserve.

I am person coming from the real world.
I see our European partners sending us drawings that invoke 2768, I do my little research. I see standard that is useful and well-written. I try to find American counterpart and I find none.
I see drawings going to China, I do my little research and see possibility that China may be leaning towards ISO. Link The article is big, so I attached little "snippet".
I see someone spreading rumors about set of relevant ISO standards costing several thousand dollars, I do my little research and find all you need for about $400.
I hear that Russian drafting standards are non-ISO, I do my little research and find them being very ISO-leaning. And you do realize that "translation" doesn't mean doing foreign language homework for tomorrow, but creating necessary reference frame to several existing or developing standards throughout big bureaucracy.
And to give credit where credit is due: there are American industries leading the world in innovation; and to lead the write their own ISO standards to spread the message: Link

May I suggest we end this discussion and switch to more productive topic?

 

[fsincox]

I have found this interesting myself. Unfortunately I have little experience with ISO, actually, and therefore am not able to contribute much.
Language seems a big barrier to me. I became interested in the DIN standards long ago; the machine tool company I was working for had a German subsidiary. I saw some of their DIN standards before they were ISO and I will tell you I could read the numbers but not any of the words, it was very tough. I got enough to see they were doing things I wanted to know about and that is about it.
I also saw the transition of the US auto industry to metric from the inside; it was not really what I would call voluntary. The real reason ASME is king is because America is king, as more is manufactured elsewhere this is changing. I think that is obvious simply by the existence of this thread. I am a late comer to the metric system myself, but, I do feel it is better for doing the kind of work we do. I was surprised and disappointed when I found my segment of the aerospace industry was still all inch.
Frank

 

[dlloydks]

To all those suggesting notes:

When we design a part, we do not know where (in what country) the product will be built or whether a particular part will be built in one of facilities or outsourced to anywhere in the world. Therefore, notes are absolutely the last resort. Notes on a drawing will have to be translated to at least 2 and maybe more languages. Much prefer a symbol that is part of some international or national standard.

 

[fsincox]

Invoke the "E" only on the size dimensions you need it on and not in the general title block notes.
Frank

 

[dgallup]

We invoked the "E" through our drafting spec because we were coming from a proprietary (British) company set of drafting standards that included the envelope principal and we did not want to change the interpretation of existing drawings. Also, every one on shop floor and in QA were used to using the envelope principal.

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

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.

 

[fcsuper]

Commentary in BS 8888:2008 about the removal of the envelop principle from the default position of the standard is interesting. They also have a special symbol for the use the principle for the whole drawing; which is actually different than the circled E.

Matt Lorono, CSWP
Product Definition Specialist, DS SolidWorks Corp
Personal sites:
Lorono's SolidWorks Resources & SolidWorks Legion

 

[fcsuper]

Checkerhater,

It's good that you are from the real world. So is everyone else on this forum. However, you do drew exteremly broad conclusions from specific examples that are not even supported by those examples.

Anyway, the world isn't so black and white, cut and dry. There's plenty of examples of industries in Europe, Canada and elsewhere where adoption of the ISO standard is far come complete (or not even attempted). There's plenty of examples of that in the US too. There certainly isn't an unstoppable march to ISO standardization that you seem to have characterized. ISO is not supplanting ASME on a massive scale. In fact, there are significant areas where ISO will point you to the "national standard". That their euphemism for "we don't have it, so use ASME". I know this, because they've told this to me, quite recently.

Matt Lorono, CSWP
Product Definition Specialist, DS SolidWorks Corp
Personal sites:
Lorono's SolidWorks Resources & SolidWorks Legion

 

[fsincox]

I am sorry I missed the part where you said you invoked it at a dimensioning and tolerancing standard level. I thought you were doing it like the ISO recommends as part of the general tolerances on the drawing sheet level, itself. Have you ever noticed people always want a standard way of going something as long as it is their "standard" way and not someone else's.
Frank

 

[fcsuper]

Frank,

An old quote, "Standards are great. Everyone has one [of their own]."

Matt Lorono, CSWP
Product Definition Specialist, DS SolidWorks Corp
Personal sites:
Lorono's SolidWorks Resources & SolidWorks Legion

 

[fsincox]

Matt,
Amen to that, thanks, I had not heard that one before.
Frank