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Recent content by Garland23

  1. Garland23

    Datum callout question

    I don't mean to sound like a technophobe, but why not just do a pen/pencil sketch and post a scan or picture? That looks like a lot of work with the mouse or stylus! :)
  2. Garland23

    How cylindicity works?

    If you understand per-unit straightness (Fig. 8-5 from Y14.5), then cylindricity is somewhat similar: imagine a regular cylindricity zone, but instead of extending for the entire length of the feature, it is only for the designated length. The zone can slide along the feature, allowing some...
  3. Garland23

    Profil tolerance check (Unequally Disposed Tolerance)

    Doug, profile is not permitted to be modified with MMC (it's not a feature-of-size thing, but merely a surface or line). I think the terminology might be confusing. The go/no-go type of gauge that might work with profile isn't what we think of as a typical go/no-go; it's more of a template...
  4. Garland23

    GD&T question on position

    I suspect they intended it to be applied to one of the holes (the thru-hole or the counterbore).
  5. Garland23

    Profile tolerance unless otherwise specified - WRT Datums vs no datums

    I'll disagree a bit. Paragraph 3.68 defines true profile as requiring basic dims to define the profiled feature itself. It does not mention anything about the feature's relationship to any datums. If a DRF is imposed but the location dimension to the profiled feature is not basic, then it...
  6. Garland23

    Profile tolerance unless otherwise specified - WRT Datums vs no datums

    It's not arbitrary; one simply has to look at how the surface (well, line) is related to the datum. And in that case it's not a basic dimension, so we are to understand that it's doing the lower-level control of orientation. That's the specific indication that you're looking for. I'm sure that...
  7. Garland23

    Profile tolerance unless otherwise specified - WRT Datums vs no datums

    Yes, it would be controlling flatness (and parallelism, and perpendicularity). But not size and not location. So that's an example of the profile symbols referencing datums yet not doing location. It is by far more common to have profile linked to its datums with basic dims, though.
  8. Garland23

    Profile tolerance unless otherwise specified - WRT Datums vs no datums

    A couple of things going on here.... Profile of a surface related to datums always controls form and orientation (unless "T" is given, which nullifies form, but that's rare). It may also control size, and it will do that if a general profile is given for the drawing, as the OP indicated...
  9. Garland23

    How to use profile of surface feature control frame to control max. protrusion?

    Write a note. There is no "GD&T" solution for your dilemma.
  10. Garland23

    threaded hole depth feature of size?

    That's why a projected tolerance zone should be used. Then the MMC idea makes perfect sense.
  11. Garland23

    understanding minimum material envelope and mating envelope on practice exam questions for GDTP preperation

    Thanks. I had done a word search in the PDF and having quotation marks around that phrase yielded nothing. Without the quotes I now easily find it!
  12. Garland23

    Concentricity vs. Runout

    The best substitute for concentricity is usually the position symbol, not a runout symbol. That's because runout is a combination of location and form errors. But concentricity didn't really check for form. Think about an oval shape: its center point could be perfectly concentric with a given...
  13. Garland23

    Symmetry Challenge

    For the ASME image, they failed to show the dots in the right-side view, and they mistakenly used the term RFS for the datum when it should have been RMB. Still studying the first one....
  14. Garland23

    One-Sided Critical/Inspection Dimension Annotation

    TK-421, what is the meaning that you intend to convey with the oval? I've often seen it used as a critical characteristic marker, meaning that it has to be inspected and tracked using statistics. But if that's the intent, then it doesn't make sense to have an oval around a single limit. The...

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