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  1. Burunduk

    Combined Zone in a material condition modified datum system

    pmarc, Are you saying that ISO consideres datum displacement as unconstrained degree(s) of freedom? I think at least per ASME Y14.5, even when there is some possible shift the degrees of freedom limited by the MMB datum feature simulator are considered constrained: "3.9 CONSTRAINT constraint: a...
  2. Burunduk

    Combined Zone in a material condition modified datum system

    ISO 5458:2018(E) seems to say that the explicit pattern specifications such as the CZ modifier are for cases where some non-redundant degrees of freedom are unconstrained. That is also reinforced by the fact that that there seem to be no examples with datum systems that constrain all DOF in that...
  3. Burunduk

    Multple single segment position

    It's a slot and the zone is 2 planes.
  4. Burunduk

    Designing a Checking Jig for Sheet Metal Hole Positions After Bending

    Usually for holes you need a gage that represents the "virtual condition" of the holes. But for more detailed and precise answer you need to show how the holes are dimensioned and toleranced. Can you embed an snip from the actual drawing by using the picture icon (I tried downloading your...
  5. Burunduk

    Cylindrical feature, datum symbol placement, in line vs not in line with dimension arrow

    greenimi, For what its worth, the only discussion in ASME Y14.5 of tangent planes to a cylinder as means for establishing a datum reference frame, is related to datum targets. It is in para. 7.24.1 in 2018 (or 4.24.5 in 2009) related to figure 7-58 in 2018 (or 4-47 in 2009). It says, " If a...
  6. Burunduk

    Multple single segment position

    That is correct. While Y14.5 covers composite profile tolerancing for a single feature, it doesn't do the same for position. So the alternative is to position within the larger tolerance to B primary and A secondary, and refine the orientation by a perpendicularity second FCF relative to B...
  7. Burunduk

    Multple single segment position

    Regarding the slot, if the concern is accurate orientation relative to datum B and a loose location control relative to A, it could be a better idea to apply a composite position tolerance relative to B primary and A secondary and refine it to B in the second segment. But if that is to be...
  8. Burunduk

    Multple single segment position

    It's a Catia thing.
  9. Burunduk

    Cylindrical feature, datum symbol placement, in line vs not in line with dimension arrow

    We need to be fair. In defense of the Y14.5 subcommittee, it can be said that the standard explicitly states that the written text is what determines the requirements, and the absence of an illustrative figure does not invalidate any specific use. And you know you're welcome to submit...
  10. Burunduk

    Cylindrical feature, datum symbol placement, in line vs not in line with dimension arrow

    The reason for the difference from a width in that sense - a width feature of size is two opposed parallel planar surfaces, and each of those surfaces could be potentially treated as a separate feature. So for a width, when the triangle of the datum feature symbol is offset from the dimension...
  11. Burunduk

    Cylindrical feature, datum symbol placement, in line vs not in line with dimension arrow

    What else is the right side, if not " placed on the outline of a cylindrical feature surface or an extension line of the feature outline " ?
  12. Burunduk

    Cylindrical feature, datum symbol placement, in line vs not in line with dimension arrow

    Here are the relevant definitions from ASME Y14.5-2018: " (d) placed on the dimension line or an extension of the dimension line of a feature of size when the datum is an axis or center plane. If there is insufficient space for the two arrows, one arrow may be replaced by the datum feature...
  13. Burunduk

    RMB for width as tertiary

    greenimi, You are right. My question, " What is the purpose of continuing to inspect a non-conforming part? " could be a bit misleading due to the implied message. Considering a policy in which all parts found to be non-conforming are scrapped, there is no point in continuing the inspection if...
  14. Burunduk

    RMB for width as tertiary

    What is the purpose of continuing inspecting a non-conforming part? However, a non-conforming datum feature should be detected when inspecting it for its tolerances and not when simulating the datum associated with it, unless the datum feature simulator is also the functional Virtual Condition...
  15. Burunduk

    RMB for width as tertiary

    What I was saying is that if you inspect the datum features first, you reject the part before the RMB datum simulator is applied, so there is little use for a rule that helps you notice some problem with the datum feature in the next step set-up.
  16. Burunduk

    RMB for width as tertiary

    pmarc, I would expect the datum features to be inspected first. Then the Regardless Material Boundary adjustable datum feature simulator to be operated to set the reference for inspecting the features that depend on the datum features. I realize under some circumstances the order of inspection...
  17. Burunduk

    RMB for width as tertiary

    Oops! Yep it's right at the beginning. But why is it important and what difference does it make if you start contracting the jaws from a separation larger than the MMB, or smaller than the MMB but still larger than the feature's Related Actual Mating Envelope?
  18. Burunduk

    RMB for width as tertiary

    I don't think so. Nothing in (e) either, or prior to that, indicates a simulator for a RMB width datum must initiate contraction or expansion from its OB/IB/MMB.
  19. Burunduk

    RMB for width as tertiary

    You mean the jaws should grab datum feature C, not B. That width (datum feature C) has an MMC of 1.005 and a position tolerance of .015 RFS relative to datums A and then B, which governs the location relative to the central hole. So the Outer Boundary for it in the A,B datum reference frame is...
  20. Burunduk

    RMB for width as tertiary

    I think I'm not sure I get it. Is it because datum feature simulator B doesn't constrain rotation? Edit: I don't think datum feature simulator C is allowed to rotate about datum axis B while contracting, if that has something to do with it.

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