Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

Register Log in
  • Congratulations TugboatEng on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Search results for query: *

  1. greenimi

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

    I don't have 3DDave's experience, knowledge and abilities to read and interpret the Y14.5 standard, but it is the first time when I hear /see someone interpreting fig 2/right side as A PLANE TANGENT to the cylinder. Never ever seen that before. Never heard about that option. Live and learn...
  2. greenimi

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

    In order to avoid unnecessary discussions and arguments I will not recommend to use fig 2's approach. There is no point to do it. Make it crystal clear (fig 1) and move on. Make it "ambiguous" (or less than clear) and then you will get people with arguments and justifications ....back and...
  3. greenimi

    RMB for width as tertiary

    Burunduk, I have A LOT of respect for pmarc, hence IF HE is questioning something then maybe "that staff" is not crystal clear.....He was questioning the approach on how to deal with non conforming datum features before so, maybe ....just maybe....the idea of stopping the inspection is not that...
  4. greenimi

    RMB for width as tertiary

    I remember you had the very same question few years ago. However I don't know what is the correct answer.
  5. greenimi

    RMB for width as tertiary

    (e) Tertiary Datum Feature: Diameter or Width RMB. For both external and internal features, the tertiary datum (axis or center plane) is established in the same manner as indicated in subpara. (d) above with an additional requirement: the theoretical cylinder or parallel planes of the datum...
  6. greenimi

    RMB for width as tertiary

    Pmarc, Do you think the "1/3 rule" is applicable here? I mean, the datum should not be established from 1/3 of the applicable surface/datum feature or something like that (if I remember correctly). Or maybe this 1/3 rule is applicable only to the primary datum (a rocker datum feature primary)?
  7. greenimi

    Datum Modifier Effects - Planar Surface

    Then how people did it pre-2009 standard? I guess instead of clarifying and be crystal clear and (there were no need to change it again in 2018) they did a half-ass job back in 09. Now we are left to pick up the pieces and no idea how to fix it.
  8. greenimi

    Datum Modifier Effects - Planar Surface

    pmarc, Yes, I understand. But then IF the datum feature shift may not be available (because supposed to be contact between datum feature B and its physical datum feature simulator) then why we are calling out B at MMB or B at LMB in the first place? Is this a chicken and the egg situation...
  9. greenimi

    nX / nSURFACES notation can be used for all the GD&T character?

    So what would be the difference between INDIVIDUALLY notation and SEP REQT (in the profile callout example you gave above)?
  10. greenimi

    Datum Modifier Effects - Planar Surface

    So if the artificial requirement is removed then on the offset planar feature MMB there will be lo longer a requirement to touch the datum feature, right? Hence why "B" it is a datum feature in the first place, if no contact, or no arresting degrees of freedom occurs ? You can spin it around A...
  11. greenimi

    nX / nSURFACES notation can be used for all the GD&T character?

    They defined the interruption.....Now, what is interrupted feature, maybe we can use the "analogy"....I don't know...... 3.39 INTERRUPTION interruption: a gap or gaps in a feature that divide it into two or more features (e.g., a slot or a groove).
  12. greenimi

    Datum Modifier Effects - Planar Surface

    pmarc, Then how, in your opinion, the cases should in figures 7-35 (BSC) and 7-36 (MMB) would look like? In some training materials (for 2009) I've seen this case called "Offset Planar Feature MMB" The specification for the two small holes is changed from A|B[BSC] to A|B-at-MMB. The physical...
  13. greenimi

    nX / nSURFACES notation can be used for all the GD&T character?

    I would say nX flatness with CF symbol is equivalent with nX profile with no datum. Flatness (regardless if you use nX or not) does not have the power to control the relationship between features. The pattern creation mechanism nX is only good with the callouts that are "powerful" enough to do...
  14. greenimi

    nX / nSURFACES notation can be used for all the GD&T character?

    Fig 12-6 /2018 "Location of circular elements" and "Location of entire surface" has the check mark on circular runout tolerance and total runout tolerance respectively. So I don't know why you are saying that "runout provides no location control". You might be right, but the difference is so...
  15. greenimi

    nX / nSURFACES notation can be used for all the GD&T character?

    pmarc, The "one" that bother me is the runout. I understood that form and orientation tolerances CANNOT create a pattern because "they" don't have a power to locate anything, but runout does have a power to locate features between each other hence runout should not have been part of the "not"...
  16. greenimi

    Perpendicularity to 3 datums

    I am not understanding this statement.......could you please explain it further? pmarc, Probably strictly talking about the question asked, you are correct. I looked a little deeper in my response (I guess you agree that the feature's location is not controlled, but should have been) Or at...
  17. greenimi

    Perpendicularity to 3 datums

    By the way CF symbol is incorrectly applied. You can use 2X before the "profile" (well future correct profile callout). You can use even composite profile to tight the relationship between the "two" top surfaces (or to make it one continuous feature). CF symbol should not have been attached to...
  18. greenimi

    Perpendicularity to 3 datums

    I would say you need a location relationship between the top surface and the datum features hence profile is the correct callout instead of shown perpendicularity (which by the way offers only orientation relationship and not location relationship)
  19. greenimi

    Symmetric to Centerline note is given to below drawing attached, need to understand how manufacturer will punch the holes at what tolerance.

    So, A primary| B-C | secondary is the way to go? Where A is a planar surface and B and C are the holes shown in the OP's picture. Then the width could be positioned to |A|B-C|
  20. greenimi

    Feature of size for 2 plane features

    Because in your example above the feature is not a FOS (neither regular or irregular). It is a surface, not a FOS. So you have to control the relationship between two surfaces.

Part and Inventory Search

Back
Top