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Recent content by greenimi

  1. greenimi

    Maximum possible contact and a single solution

    Per the 2019 Math standard """"""This revision includes a new stabilization definition for irregularities on datum features specified at RMB, which provides an alternative to the candidate datum set. SC5 had moved toward the concept of a single-stable solution that minimizes the separation...
  2. greenimi

    Maximum possible contact and a single solution

    Do you kow how ISO GPS is treating this pattern RMB issue? I would even ask pmarc for the rescue ---if you are reading this discussion 🙏 I found this on ISO5459 and states ..." with objective function "MINMAX" to minimize, simultaneously and globally, the maximum distance between......" Is...
  3. greenimi

    Perpendicularity callout with curved datum

    Pmarc, For the sake of discussion and learning purpose, let me ask you this question: What wold be the geometrical difference between your solution (above) and a profile with tangent plane modifier to A( datum feature "A" being the Ø4mm hole) I am thinking something similar to fig 12-15 (2018)...
  4. greenimi

    Perpendicularity callout with curved datum

    I am thinkg the other way around. make the hole a datum feature and then orient the curved surface to the hole with the perpendicualrity and T modifier. I am looking to establish a relationship between the curved surface and the hole hence a slight adjustement to get this relationship is what I...
  5. greenimi

    Perpendicularity callout with curved datum

    Or maybe perpendicularity works, but adding the tangent plane modifier could be something to consider...or maybe not...
  6. greenimi

    Maximum possible contact and a single solution

    I agree with you. With only one caveat: We have to understand what the theory -read "the standard"- requires (and what does not require) - before we can apply such of said theory in any sort of practical way. We are debating/ clarifying here mostly our individual understandings of the theory...
  7. greenimi

    Maximum possible contact and a single solution

    So, if "The true geometric counterparts shall expand or contract simultaneously" should NOT have mentioned in 7.12.4, then how the end user would have understood the DEFAULT condition as being "simulaneously" (simultaneity) and not being the "maximum possible contact" ? Other figures RMB...
  8. greenimi

    Maximum possible contact and a single solution

    Burunduk, For some reason I feel like you are beating around the bush and avoid giving me a straight answer about YOUR opinion Are you of an opinion that if one datum feature simulator stops expanding or contracting then THE OTHER shall stop expanding or contracting (even the second datum...
  9. greenimi

    Maximum possible contact and a single solution

    I have seen your thread, but does not solve my question about patterns at RMB.
  10. greenimi

    Maximum possible contact and a single solution

    Let me ask you a direct question: Per 2018 the default stabilization procedure has been changed from candidate datum set to a single solution that minimizes the separation between the features and the TGC. Is this new procedure more clear than the old one regarding the pattern feature at RMB? If...
  11. greenimi

    Maximum possible contact and a single solution

    Yes, I found this thread https://www.eng-tips.com/threads/inclined-datum-and-degrees-of-freedom.526559/#post-9052343 It is for the "single solution" and the " "constrained least squares"" Do you see any "other" discussions relevant to this subject? But my main question stil remains: Is it...
  12. greenimi

    Maximum possible contact and a single solution

    So you are of an opinion that if one datum feature simulator stops expanding or contracting then THE OTHER shall stop expanding or contracting (even the second datum feature simulator did not reach its full potential of maximum possible contact)? Is my understanding correct? So basically you...
  13. greenimi

    Maximum possible contact and a single solution

    As i stated in the previous thread: If one simulator stops contracting to get the smallest perfectly formed cylinder circumscribed around the actual "as made" feature, what is going to happen with the other simulator? This second simulator will stop too or will keep contracting? That was my...
  14. greenimi

    Maximum possible contact and a single solution

    So are the simulators independent from each other?
  15. greenimi

    Maximum possible contact and a single solution

    Per ASME Y14.5-2018 7.12.4 Pattern of Features of Size RMB When RMB is applicable in a feature control frame to common datum features of size used to establish a single datum, the true geometric counterpart of each feature shall be fixed in location relative to one another. The true geometric...

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