Profile to a single datum... (Whys this so difficult to understand?)

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Profile to a single datum... (Whys this so difficult to understand?)

    Ok, same part I have been programming for a while now. I understand the difference in legacy and xact, I like legacy though.

    I have it aligned, ABC, plane>circle>circle...done deal.

    Bottom surface (shaped like an "L" is datum D...the top of the bottom surface...has a profile callout...profile, .05 to datum D.

    I understand when it doesnt reference any datums its form only, but since this references datum D, and Im aligned to A, B and C...when I select profile, do I use form only, form and location? or is there a best fit required here using Datum D.....any input is worth its weight in gold..
    Browne & Sharpe Global Advantage 12|22|10
    PCD 2012 MR1 CAD++

  • #2
    So the 'bottom' of the bottom of the "L" is datum "D" and you have a profile called out on the top of the bottom of the "L" to D.

    The 'upright' of the "L" has no part of this, just the _ of the L, with the bottom of the _ being datum "D" and the profile called out on the top side of the _

    Level and origin to the bottom of the _ and check the top of the _ and use form and location.
    sigpic
    Originally posted by AndersI
    I've got one from September 2006 (bug ticket) which has finally been fixed in 2013.

    Comment


    • #3
      Form and location and the distance form -B- to the 'top of the bottom' would be your basic dim.

      If you are not sure about the GD&T just use Xact. In my experience Xact interprets GD&T well, not everything is 100% good, but profiles are.

      Comment


      • #4
        If Matt restated the question correctly, I agree. If he did not, a sketch may be in order to adequately describe the part.
        sigpic

        Comment


        • #5
          Man Id give anything to know these things like you guys do, one day I guess...
          Browne & Sharpe Global Advantage 12|22|10
          PCD 2012 MR1 CAD++

          Comment


          • #6
            Patience, young grasshopper
            sigpic...engineering

            Comment


            • #7
              Ok guys, so I did as suggested, measured D as a plane, then top surface as a plane. I leveled and translated to the D datum, and then dimensioned profile, form and location of the top surface to D. +/- .25. And it measured in tolerance..but my question is, what is happening here?

              By leveling and translating to D, when doing the pofile dimension, I only select the surface that Im dimensioning, hows it know to compare to D....? Is that what its doing?

              If I didnt level and translate to D, whats it comparing to then? Is it only comparing the profile to the leveled axis?
              Browne & Sharpe Global Advantage 12|22|10
              PCD 2012 MR1 CAD++

              Comment


              • #8
                Originally posted by Mike_B View Post
                Ok guys, so I did as suggested, measured D as a plane, then top surface as a plane. I leveled and translated to the D datum, and then dimensioned profile, form and location of the top surface to D. +/- .25. And it measured in tolerance..but my question is, what is happening here?

                By leveling and translating to D, when doing the pofile dimension, I only select the surface that Im dimensioning, hows it know to compare to D....? Is that what its doing?

                If I didnt level and translate to D, whats it comparing to then? Is it only comparing the profile to the leveled axis?
                It's like you set the part on a granite plate on the Datum D surface and swept the top surface with an indicator.

                It's comparing to D, because you leveled and translated to it.

                If you hadn't, then it would be comparing to ABC which you previously aligned to.
                "This is my word... and as such is beyond contestation."

                Comment


                • #9
                  Legacy is looking at the latest alignment.

                  Comment


                  • #10
                    Ok thats what I was thinking guys, Level 2 opened my eyes to Best Fits and these alternate alignments, so Im treading lightly til I get them figured out.
                    Browne & Sharpe Global Advantage 12|22|10
                    PCD 2012 MR1 CAD++

                    Comment


                    • #11
                      Originally posted by Nano Vujkovic View Post
                      Legacy is looking at the latest alignment.
                      So, in theory, using Xact and defining datums, this dimension is handled correctly without having to make sure the alignment is set correctly as in Legacy mode, correct?
                      Browne & Sharpe Global Advantage 12|22|10
                      PCD 2012 MR1 CAD++

                      Comment


                      • #12
                        Originally posted by Mike_B View Post
                        So, in theory, using Xact and defining datums, this dimension is handled correctly without having to make sure the alignment is set correctly as in Legacy mode, correct?
                        In theory, yes, but every click box in Xact must be checked properly, there are several. In the version I used (4.2 mr1), there were dimensions when using Xact that are not handled properly ALL THE TIME, so I never used it for anything. If I remember correctly, Hexagon later stated NOT to use Xact in versions previous to 2012 (I think). Perhaps someone else can confirm or tell me I am mistaken. It's probably in a thread on this forum.

                        If Xact is the way you choose, I HIGHLY recommend reading this thread by Wes Cisco:
                        http://www.pcdmisforum.com/showthrea...ht=Xactmeasure
                        Last edited by ir a programmer; 02-25-2015, 08:20 AM.
                        sigpic

                        Comment

                        Related Topics

                        Collapse

                        • merlin1968
                          Profile of a surface - nominal is 0
                          by merlin1968
                          I am having a time trying to get this measure correctly. I have a part that is profile of a surface of datum .030 tol in relation to A,C. Datum D should...
                          08-31-2010, 10:47 AM
                        • AuRules
                          Profile
                          by AuRules
                          Needing some clarification, I'm saying that the profile in the picture is for form and location due to the location constraints from datum A & B,...
                          06-13-2019, 10:54 AM
                        • mgroll77
                          Profile Differences
                          by mgroll77
                          I'm trying to report the profile of a surface using a constructed feature set from 58 vector points.

                          When I report the profile using Legacy,...
                          06-18-2013, 09:58 AM
                        • Wingman
                          Profile rules
                          by Wingman
                          Our company applies profile as such:
                          When there is no Datum Reference then we use profile to control form.
                          When there is a Datum Reference...
                          02-10-2009, 10:39 AM
                        • RSNICKER
                          Double profile
                          by RSNICKER
                          Does anybody know if the 4.2 software can measure a double profile callout.
                          I have a profile of two radii with a tolerance of 4 to datum B and...
                          06-18-2009, 12:53 PM
                        Working...
                        X