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Recent content by Garland23

  1. Garland23

    GD&T - Feature Control Frame attached directly to a basic dimension.

    Since profile of a surface is applied to a surface, the FCF should be tagged to the surface, not a basic dimension.
  2. Garland23

    Multple single segment position

    Makes sense. I glanced too quickly!
  3. Garland23

    Multple single segment position

    And... perhaps both callouts should have included a diameter symbol before their respective numbers.
  4. Garland23

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

    I too would not recommend it, but I think it's pretty clear in meaning the axis. Definition (e) does mention an extension line of a cylinder (which the right-hand figure shows) and (e) even says that it can be separated from the size dimension (the arrows). It doesn't say that such usage must...
  5. Garland23

    Perpendicularity to 3 datums

    You didn't describe the feature that the perp tolerance is applied to. But if it's a surface then yes, profile of a surface might be an alternate way to do things. But if it's a hole/pin or other "feature of size" then I wouldn't change the symbol to profile because that would change the...
  6. Garland23

    Datum Modifier Effects - Planar Surface

    Hi.... First of all, I think you're referring to just Fig. 4-31 and its sub-figures of 4-31(a), 4-31(b), and 4-31(c). They're all on page 73 of that 2009 edition. Regarding your main question, in that third example where they invoke MMB, yes one point of contact (minimum) is required. The...
  7. Garland23

    Hex hole as a datum feature

    Suppose we were dealing with a square peg/hole: If it had a similar dimension of .753 +/- xxx and the word SQUARE, would you also say that its definition is lacking? I wouldn't. (I know there's a square symbol, but I'm just posing this question to keep it analogous to the HEX question.)
  8. Garland23

    Hex hole as a datum feature

    Since the drawing clearly says "HEX," I think it's clear that the datum is intended to be created from the full six sides, not just the two flats being pointed to. In the ASME Y14.5 standard, Figure 7-3 shows two interesting examples at the bottom of that graphic. Although they are rounded, not...
  9. Garland23

    Maximum material condition on circular datum

    That's true for the boundary/simulator/counterpart; of course. But the initial question (highlighted in yellow in the first post) was whether the modifier affected DATUM B -- the "theoretical axis of the inner hole," to use the OP's phrasing. Thus, it's probably best to answer the question based...
  10. Garland23

    Maximum material condition on circular datum

    I'll be nitpicky -- that's not quite true. For a feature being toleranced with position at MMC (the four holes), that would be true. But a datum is always a theoretical plane, axis, point, or combo of those. With MMB, it just means that the theoretical axis is one that's derived from the feature...
  11. Garland23

    AVG and F symbol - fig 8-14/2018

    jassco, according to paragraph 8.4.3 of the 2018 standard, I think that the AVG notation already tosses R#1 out the window. So I'd still say that the F is not needed.
  12. Garland23

    AVG and F symbol - fig 8-14/2018

    I don't think the F is needed in Fig. 8-14, because the restraint note is clearly meant only for the circular runout check and nothing else.
  13. Garland23

    Is there a preferred true position standard?

    There is no way to say if a tolerance is tight or not, without understand the function and the mfg process juxtaposed to each other. (What is the purpose of the clip?) Why is .005 inch a tight tolerance? What if we were making something at a microscopic level? Then it would be a huge...
  14. Garland23

    Can Flatness have an associated Basic Dimension

    Perhaps the flatness callout is tagged to a surface that also happens to be a datum feature. Then, you could indeed locate a hole (position) from that "flatnessed" surface.
  15. Garland23

    Slot pattern Datums

    Attached is an example of a slot-type shape being used as a datum feature, from Fig. 7-3 of the ASME Y14.5 standard. However, since you are asking about two slots, you'd have to be careful not to overconstrain the degrees of freedom. Perhaps you could reference B and C with the "M" modifier...
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