Talk:IT Grade

Micron vs Micrometre

Fair enough Editore99. Micron is a slightly archaic usage being formally discouraged in the 60's. And since you used the British spelling, micrometre and not the American spelling, micrometer maybe the distinction between a millionth of a meter and a device for measuring small things is preserved, especially in context. Micron is still commonly used to denote .001mm and to avoid confusion. I will not undo your change. However, Micron is technically correct, if not officially. Dachande 22:24, 14 May 2007 (UTC)

k

$k=10^{0.2(ITG-1)}$ ? (yes/no)

According to your re-work, yes for k*i, but I don't know about k*I. Dachande 22:17, 30 May 2007 (UTC)

*nominal dimension less or equal to 500 = i

*nominal dimension greater than 500 (up to 4000) = I

(I'm looking for math formula behind IT grade's tables.)

Everything I was ever taught indicates that the formula is constant. The referenced table from Engineer's Edge backs me up. Please include a reference when you post the information about k*I. Dachande 02:28, 31 May 2007 (UTC)

Engineering Category

INWIND, what is your objection to this page being labeled ENGINEERING in addition to measurement? I think it should be both since IT Grade is based on ENGINEERING MEASUREMENT, not just general measurement, like a ruler or a protractor. It directly relates to the engineering measure of Industrial mass production process capability.

So, please state your thoughts on the matter in the talk page, INSTEAD of just reverting my addition. I will not revert your revert, but that just gets obnoxious. But please leave your thoughts here. Who knows, maybe you sway me. Thanks. Dachande 20:22, 5 November 2007 (UTC)

Grade

Is "Grade" supposed to be capitalized? My gut instinct says no but I'm not familiar with it. --Wizard191 (talk) 02:32, 30 March 2008 (UTC)

Revert removal of reference

I undid a revision in which an esteemed co-editor removed my reference to a U of M Professor's course notes. I will look into where he got it from when I get some spare time, but that is the source I'm quoting. It is verifiable, it's legit as demonstrated by the fact that the equation will match the uncontested Engineer's Edge table. And I see no reason for it be removed. Updated with the original source, yes. But not arbitrarily removed. IF you remove it to replace it with a more original and better source, fine. I have no qualms with that. Just cuz you can't link to something does not make it unverifiable. If you went to the University of Michigan, North Campus, into GG Brown Laboratories and found Professor Sridhar Kota, and got his course notes, you'd find this definition and equation. I know, I took and TA'ed the course.

Anyway, Like I said, I will try to find the original, more widely published version that I am sure Prof. Kota cited. Dachande (talk) 16:25, 4 June 2008 (UTC)

No offense but did you read WP:V? It says: Articles should rely on reliable, third-party published sources with a reputation for fact-checking and accuracy. I don't care about the "linkability" of a source. I cite books all of the time. I'm sure that the equation is legit, but the reference just doesn't cut it. Second, you seem to have a conflict of interest because you were his TA. Please don't let this bias your judgment. In any case it should easy to find a better reference for it. --Wizard191 (talk) 17:46, 4 June 2008 (UTC)

Alright. I concede the conflict of interest point freely. Clearly, you're right on that one. I don't think I'm doing anything with it, but I am COI. I am not trying to plug him or the class, (though I may be doing so...) That's just the source I had. I will go look for the source he used in his notes, which certainly would be inline with WP:V. Provided I can find it. I would honestly prefer someone with knowledge of the ISO standard this phenomenon came from got the source for it. I don't know that the equation would be in the standard though. As for the claims of violating WP:V I present this defense of my character:

1. The article is NOT about Sridhar Kota, U of M, ME 452, or me. Therefore, He and his course notes would be third party.
2. As a tenured Professor at a Major University, he is by definition Published, reliable, and known for fact-checking and accuracy. (I admit this is the weakest argument I make, but he IS teaching the material to the students who will probably be designing the next car you drive.)
3. This article is NOT relying on this reference. It has the perfectly legit reference to Engineer's Edge for the formulation and interpretation (more or less). I added the reference to substantiate the equation and formulation as opposed to the non-sense some unsigned user added a while back. Go through the edit history and you'll see some real non sense. By putting a reasonably (though admitedly imperfect) legit reference on it, I hoped to prevent that kind of nonsense. (Aside: The unsigned user's formulations didn't work and I'm not sure he was talking about the samething.)

All that being said, Here is the summary of my stance. Yes - article needs more/better references, but no that reference is not a violation of Wikirules. Until a better reference for that stuff comes up, and I will try to remember to look for it, it should stay.

Thank you for your input I look forward to discussing this further as I am sure you will respond to this. Dachande (talk) 18:43, 4 June 2008 (UTC)

I added a link to the ability to purchase the ISO 286 Standard. They cost quite a bit of money, and it was the best source I could get without resorting to course notes. I really and truly wish I could do better in terms of finding good sources. But I think the sources are good for right now. I have the lecture notes so I can verify that the equation is legit to the notes, but I cannot prove that the notes are legit to the standard without purchasing the standard, which I am not willing to do for wikipedia. If I come across anything else of value I will add it.Dachande (talk) 02:10, 5 June 2008 (UTC)

I want to preface this with the fact that I think we are on the same page; that we both agree that it needs a better source. I'm going to reply to your POV of a legit source, strictly to just share my thoughts, and I just want to leave it at that. I'm not trying to change your mind or anything, I just want to share my POV on the idea of a verifiable source (and perhaps I'm wrong). I'll even admit that through your explanation that I think the source is better than I had first viewed.

My points are:

1. When I think 3rd party source I think of it in the sense that it's published by a 3rd source, and not that the source is 3rd party from the article topic. Perhaps I'm just viewing the 3rd party idea from the wrong stance.
2. I don't know if just being a professor qualifies you as published. If this were true then why would they even go through the pain of publishing papers? Also, I've had professors that have had notes that are wrong and in contradiction to printed text books. I realized that this is much less likely if he's tenured and taught the class previously, but still a point. Moreover, course notes are not required to be peer reviewed like publications.

None the less, I'll back down and let it stay until a better source can be found. I do want to note that I did some research yesterday and couldn't come up with anything for equations, at least on the internet, my Shigley book and Machinist handbook book at work. --Wizard191 (talk) 15:03, 5 June 2008 (UTC)

If the equation is in the ISO Standard, which I am unwilling to verify because of the cost, then it's all set. If it's not, I would consider the course notes of a tenured professor at a major university to be reasonably close to sufficient. Especially since the equation matches the engineer's edge chart. If you use the equation, you will get the results on the third party reliably published source. So I think it's covered. And if it's not, someone will find a better source eventually. Thank you for your reasonableness. I appreciate the debate and your checking my COI. Plus, you've listed a couple places that definitely DON'T have the equation so maybe that'll help someone. Dachande (talk) 00:09, 6 June 2008 (UTC)

Engineer's Edge

Ok, um, Engineer's Edge seems to have adopted our text for their site. (See link to IT Grade Charte) I don't believe when I created this page that I took the text vebatim from EE. I swear I think I wrote it up from memory. I have no documentation of this, but I know I did. And so I am convinced they took the text and formula from the wikipedia article and used it. No problem but I want to be clear that I am pretty certain that can't be a reference because they took it from us. Circular Reference and all that. Just and FYI and a CMA in case they get mad that "we" took "their" text. Dachande (talk) 16:55, 12 August 2008 (UTC)

I'm pretty sure you are right. I remember looking at that link a couple of months ago when I was weeding out spam links and previously it was just the chart. Good heads-up. --Wizard191 (talk) 17:49, 12 August 2008 (UTC)

Table of tolerance grades

Forgive my possible ignorance on this question, but is it feasible to construct a table in this article based on the table located at the Engineer's Edge website? The table they have provided is in a bitmap format and barely legible. If we could convert it to a HTML table it could be very useful. Would fair use rights allow us to do that? --Dslc (talk) 19:32, 14 August 2011 (UTC)

I'm not sure they'd care either way since, as noted above, I think they stole the text of the wikipedia article verbatim for that page. I'm not saying we should steal it back, so to say, but I think if we created a table, similar to theirs, using the formula above, it'd be a new creation. COPYING their bitmap is questionable, creating your own table seems fine. Just my two cents. Dachande (talk) 20:18, 16 August 2011 (UTC)

Formula for T

How this formula is arrived at?

It may not be an arbitrary formual.

What is the background of this formula? —Preceding unsigned comment added by 61.2.228.79 (talk) 15:47, 8 May 2009 (UTC)

Honestly, I do not know. I would be very interested in a derivation of how it works, but I have never seen one. I doubt the ISO standard would have it. Definitely a welcome piece of knowledge if someone can include it. Dachande (talk) 13:02, 15 May 2009 (UTC)

The equation given in this article seems to be incorrect and misleading and not in agreement with ISO 286-1:2010! The standard does use an equation, but instead includes 'Table 1 — Values of standard tolerance grades for nominal sizes up to 3 150 mm.' This table, not any formula, is the normative definition per the wording of the specification:

"The standard tolerance grades are designated by the letters IT followed by the grade number, e.g. IT7. Values of standardised tolerances are given in Table 1. Each of the columns gives the values of the tolerances for one standard tolerance grade between standard tolerance grades IT01 and IT18 inclusive. Each row in Table 1 is representing one range of sizes. The limits of the ranges of sizes are given in the first column of Table 1."

Table of international tolerances

I've added a table with the actual data values from ISO 286-1:2010. I think this resolves a number of issues raised above. Burt Harris (talk) 18:16, 27 February 2021 (UTC)

I reverted a change to the table which broke the formatting. If you have a correction to the table and can't get it to format correctly, drop me a note on my talk page describing the change needed. Burt Harris (talk) 02:01, 20 September 2021 (UTC)