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Quick question About ISO.....

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
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  • Ok... thanks to 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.
  • 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... ;-)
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