If a Blueprint calls for ASME Y14.5 wouldn't this be the standard rules apply. How would I know if and when to apply ISO? I have yet to see anything on a blueprint stating this. The reason I bring this up is for the good old Profile callout. Before I make an argument, I want to cover all my resources. Customer already claims in an email that PC-DMIS is not capable of doing this. I and everyone on here already that's horse_S_H_I_T. But its Friday and I'm ready to P_I_S_S someone off
Vinni, oh that quote is from that Mathematical Definition publication that you have, that's why i dont see it in the Dim & Tolerancing standard. Yeah, the way that sounds, it could be taken to mean, "dont take that one greatest deviation number and multiply it by two and report it as your profile result". Whats the name etc of that publication?
Ok... thanks to
KIRBSTER269 I now have a version of the ASME Y14.5.1M-1994 Mathematical Definition of Dimensioning and Tolerancing Principles to study. Kirb, you quoted from page 40 before, "Note that no single actual value may be calculated for comparison to the tolerance value in the feature control frame" but I think the part just above that is more significant. this is
Section 6.5 Profile Control. on page 39 on sub-paragraph C it says (quoted in
blue):
(c) Actual value. <this is it right? this is where what we would actually report is defined right?>
For both unilateral and bilateral profile tolerances two actual values are necessarily calculated: one for surface variations in the positive direction and one for the negative direction. For each direction, the actual value of profile is the smallest intermediate tolerance to which the surface conforms. so what does that MEAN?
it seems to me that you look at your measured points as they are arrayed around your nominal profile line.
For bi-lateral profile....
Imagine expanding your tolerance zone, from 0,
both sides at once,
Until the zone is wide enough to enclose your greatest deviated point.
I tried to make a video that illustrates what I mean, see what you think.[video]
https://youtu.be/YWKTFOg6N0A[/video]
Be gentle critics! This is my first youtube video!! the link again is
https://youtu.be/YWKTFOg6N0A If you were to expand a unilateral zone, you'd just be expanding it on one side, but if you are expanding a bi-lateral zone, you'd be expanding it from BOTH sides at the same time wouldn't you? In my video example, the greatest deviation is at +3 but if you expand the zone on both sides, it would report as 6.
And therefore the actual value you'd report would be a bi-lateral zone wide enough to enclose your greatest deviation.
no its says actual value, not imaginary values. 1 Actual in the positive (highest reading from 0) and 1 Actual in the negative(lowest reading from 0). You are not expanding equally. There is nothing in that quote that says this. But what you're explaining is exactly how it is in ISO 1101
I can see how it could be interpreted either way. Your way is reasonable, expanding each side of the zone until it touches the maximum deviation on each side = min+max. I think you could get my meaning out of it too if you work at it... Maybe my understanding is what they MEANT to say... ;-)
That's why I said that's how they go into great detail like that in the ISO 1101 standard. I can see both ways. But each one explains it quite differently. The ISO says to treat it like an envelope and it even says that several times, everything is inside the envelope. Asme is inside the envelope looking out. I would suggest you purchasing the ISO 1101, you would be saying "this is exactly how I see it"
We dont have to measure anything that' drawn to ISO. I've got quite a ways to go before I am satisfied with my understanding of ANSI. Study a standard that I'm not going to use? aaagghhh!!! :scream;
I know how you feel, but I will do my D_a_m_n nist to cover every detail to satisfy the customer. I look at everything on the blueprint every note make sure I'm not missing anything. and even after posting it on here. Everyone voicing there knowledge on the matter. It was still up to me to do the grunt work. Even if its buying a book that I don't need. It's in my back pocket and I can share with others who might need to know.
