H E L P ! ! ! Please!

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

  • H E L P ! ! ! Please!

    I have a horrible part. Crazy design, very tight tolerances, hard to manufacture, hard to measure, etc. After several phone conversations with the customer's CMM programer I finally took a part he had reject to his place with me this morning. The idea was to watch him run it on his Sheffield with MeasureMax and go step by step to figure out why I am getting a measurement .0007 different from what he gets. This is one axis of a .002" trueposition callout. So he tells me that when capturing datums per ANSI Y14.5 etc that I should use Minimum Circumscirbed and Max Inscribed instead of least squared. I thought about it for a minute or two and agreed with the logic. So I come back to my place and try to make my program as identical to his as possible. I measure a circle on one end of the part. (cylinder in v-block). Then I measure a circle on the other end. Create a 3d line between them. Level and origin on the line. I have done this hundreds of times and never a problem. A couple more hits to finish up and create my manual alignment. Then I go back and measure those same two diameters DCC with Minimum Circubscribed and I get the location off by .1" in Z. WTF I tried Max Inscribed and it does not do this. Someone please show the me the stupid thing I am overlooking.
    sigpic"Hated by Many, Loved by Few" _ A.B. - Stone brewery

  • #2
    Check the form of the corcles. I bet they are oval or egg shaped. When using max or min, the circle is constructed with the largest that will fit in and the smallest that fit over.
    sigpic GDTPS - 0584

    Comment


    • #3
      http://www.pcdmisforum.com/attachmen...6&d=1186661881
      Lately, it occurs to me
      What a long, strange trip it's been.

      2017 R1 (Offline programming)

      Comment


      • #4

        This link does not work for me.

        I have checked the form, they are round within .001" how does that calculate to moving the center .1"???


        sigpic"Hated by Many, Loved by Few" _ A.B. - Stone brewery

        Comment


        • #5
          Yeah, .100 does seem a bit extreme.... something else is going on there.
          Post code?
          Lately, it occurs to me
          What a long, strange trip it's been.

          2017 R1 (Offline programming)

          Comment


          • #6
            STARTUP =ALIGNMENT/START,RECALL:, LIST= YES
            ALIGNMENT/END
            MODE/MANUAL
            MOVESPEED/ 40
            LOADPROBE/5X100
            TIP/T1A0B0, SHANKIJK=0, 0, 1, ANGLE=0
            FORMAT/TEXT,OPTIONS,ID,HEADINGS, , ;NOM,TOL,MEAS,DEV,OUTTOL, ,
            PROBECOM/ON
            WORKPLANE/YPLUS
            COMMENT/OPER,NO,
            ,
            ,THIS PROGRAM WILL USE THE 5X100
            ,AND THE TIP TO CHECK THE
            ,SEQ 70 MILL WORK. THIS PROGRAM
            ,WILL RUN ON A COMPLETED PART.
            ,
            ,PART ON SMALL V-BLOCKS
            ,LEVEL AND ALIGN TO MACHINE AXIS
            ,
            ,
            ,SEE PICS
            ,
            ,CREATED 3.7MR3 8-23-06 -W.C.
            ,
            ,
            ,
            ,
            COMMENT/OPER,NO,
            ,
            ,WITH THE Y AXIS LOCKED TAKE 3 HITS
            ,AROUND DATUM Z FROM RIGHT TO LEFT
            ,
            ,
            ,
            ,
            CIR1 =FEAT/CIRCLE,RECT,OUT,LEAST_SQR
            THEO/6.5683,24.5069,-22.5684,0,1,0,5.4683
            ACTL/6.5683,24.5069,-22.5684,0,1,0,5.4683
            MEAS/CIRCLE,3,WORKPLANE
            HIT/BASIC,NORMAL,9.3018,24.5069,-22.5083,0.9997586,0,0.0219728,9.3018,24.5069,-22.5083,USE THEO = YES
            MOVE/CIRCULAR
            HIT/BASIC,NORMAL,6.5992,24.507,-19.8345,0.0112941,0,0.9999362,6.5992,24.507,-19.8345,USE THEO = YES
            MOVE/CIRCULAR
            HIT/BASIC,NORMAL,3.8466,24.5069,-22.3076,-0.9954383,0,0.0954078,3.8466,24.5069,-22.3076,USE THEO = YES
            ENDMEAS/
            COMMENT/OPER,NO,
            ,
            ,WITH THE Y AXIS LOCKED TAKE 3 HITS
            ,AROUND DATUM A FROM LEFT TO RIGHT
            ,
            ,
            ,
            ,
            CIR2 =FEAT/CIRCLE,RECT,OUT,LEAST_SQR
            THEO/6.5653,17.6194,-22.5673,0,1,0,5.6589
            ACTL/6.5653,17.6194,-22.5673,0,1,0,5.6589
            MEAS/CIRCLE,3,WORKPLANE
            HIT/BASIC,NORMAL,3.7362,17.6194,-22.5283,-0.9999048,0,0.0138015,3.7362,17.6194,-22.5283,USE THEO = YES
            MOVE/CIRCULAR
            HIT/BASIC,NORMAL,6.5464,17.6195,-19.7379,-0.0066936,0,0.9999776,6.5464,17.6195,-19.7379,USE THEO = YES
            MOVE/CIRCULAR
            HIT/BASIC,NORMAL,9.3892,17.6194,-22.3901,0.9980377,0,0.0626162,9.3892,17.6194,-22.3901,USE THEO = YES
            ENDMEAS/
            COMMENT/OPER,NO,
            ,
            ,TAKE A SINGLE HIT ON DATUM C AT
            , EXACTLY 12 O'CLOCK
            ,
            ,
            ,
            PNT1 =FEAT/POINT,RECT
            THEO/6.5356,15.3496,-19.904,0,-1,0
            ACTL/6.5356,15.3496,-19.904,0,-1,0
            MEAS/POINT,1
            HIT/BASIC,NORMAL,6.5356,15.3496,-19.904,0,-1,0,6.5356,15.3496,-19.904,USE THEO = YES
            ENDMEAS/
            COMMENT/OPER,NO,
            ,
            ,
            ,
            ,CLEAR PROBE ABOVE PART FOR DCC
            ,
            ,
            ,
            ,
            WORKPLANE/ZPLUS
            MANLINE =FEAT/LINE,RECT,UNBND
            THEO/6.5683,24.5069,-22.5684,-0.0004277,-0.9999999,0.000161
            ACTL/6.5683,24.5069,-22.5684,-0.0004277,-0.9999999,0.000161
            CONSTR/LINE,BF,3D,CIR1,CIR2,,
            OUTLIER_REMOVAL/OFF,3
            FILTER/OFF,WAVELENGTH=0
            YAXISLINE =FEAT/LINE,RECT,UNBND
            THEO/6.5668,21.0632,-22.5679,-0.0117253,0,0.9999313
            ACTL/6.5668,21.0632,-22.5679,-0.0117253,0,0.9999313
            CONSTR/LINE,BF,2D,MANLINE,PNT1,,
            OUTLIER_REMOVAL/OFF,3
            FILTER/OFF,WAVELENGTH=0
            MANALIGN =ALIGNMENT/START,RECALL:STARTUP, LIST= YES
            ALIGNMENT/LEVEL,ZPLUS,MANLINE
            ALIGNMENT/ROTATE,YPLUS,TO,YAXISLINE,ABOUT,ZPLUS
            ALIGNMENT/TRANS,XAXIS,MANLINE
            ALIGNMENT/TRANS,YAXIS,MANLINE
            ALIGNMENT/TRANS,ZAXIS,PNT1
            ALIGNMENT/END
            DIM D1= LOCATION OF CIRCLE CIR1 UNITS=IN ,$
            GRAPH=OFF TEXT=OFF MULT=10.00 OUTPUT=BOTH
            AX NOMINAL +TOL -TOL MEAS DEV OUTTOL
            X 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
            Y 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
            D 5.4683 0.0000 0.0000 5.4683 0.0000 0.0000
            END OF DIMENSION D1
            DIM D2= LOCATION OF CIRCLE CIR2 UNITS=IN ,$
            GRAPH=OFF TEXT=OFF MULT=10.00 OUTPUT=BOTH
            AX NOMINAL +TOL -TOL MEAS DEV OUTTOL
            X 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
            Y 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
            D 5.6589 0.0000 0.0000 5.6589 0.0000 0.0000
            END OF DIMENSION D2
            MODE/DCC
            WORKPLANE/ZPLUS
            MOVE/POINT,NORMAL,3,4.5,0
            DATUM_A_1 =AUTO/CIRCLE,SHOWALLPARAMS = YES,SHOWHITS = NO
            THEO/0,0,-2.26,0,0,1,5.66,0
            ACTL/0,0.1023,-2.26,0,0,1,5.6551,0
            TARG/0,0,-2.26,0,0,1
            THEO_THICKNESS = 0,RECT,OUT,CIRCULAR,MIN_CIRCSC,ONERROR = NO,$
            AUTO MOVE = NO,DISTANCE = 0,RMEAS = None,None,None,$
            READ POS = NO,FIND HOLE = NO,REMEASURE = NO,$
            NUMHITS = 17,INIT = 0,PERM = 0,SPACER = 0,PITCH = 0,$
            START ANG = 0,END ANG = 180,DEPTH = 0,$
            ANGLE VEC = 1,0,0
            MOVE/POINT,NORMAL,-3,0,-3.06
            DATUM_A_2 =AUTO/CIRCLE,SHOWALLPARAMS = YES,SHOWHITS = NO
            THEO/0,0,-3.06,0,0,1,5.66,0
            ACTL/0,0.1023,-3.06,0,0,1,5.6553,0
            TARG/0,0,-3.06,0,0,1
            THEO_THICKNESS = 0,RECT,OUT,CIRCULAR,MIN_CIRCSC,ONERROR = NO,$
            AUTO MOVE = NO,DISTANCE = 0,RMEAS = None,None,None,$
            READ POS = NO,FIND HOLE = NO,REMEASURE = NO,$
            NUMHITS = 17,INIT = 0,PERM = 0,SPACER = 0,PITCH = 0,$
            START ANG = 180,END ANG = 0,DEPTH = 0,$
            ANGLE VEC = 1,0,0
            DATUM_A_LINE=FEAT/LINE,RECT,UNBND
            THEO/0,0,-2.26,0,0,-1
            ACTL/0,0.1023,-2.26,0.0000223,-0.0000379,-1
            CONSTR/LINE,BF,3D,DATUM_A_1,DATUM_A_2,,
            OUTLIER_REMOVAL/OFF,3
            FILTER/OFF,WAVELENGTH=0
            DAT_A_LINE_LEVEL_AND_ORIGIN=ALIGNMENT/START,RECALL:MANALIGN, LIST= YES
            ALIGNMENT/LEVEL,ZMINUS,DATUM_A_LINE
            ALIGNMENT/TRANS,XAXIS,DATUM_A_LINE
            ALIGNMENT/TRANS,YAXIS,DATUM_A_LINE
            ALIGNMENT/END
            DIM D3= LOCATION OF CIRCLE CIR1 UNITS=IN ,$
            GRAPH=OFF TEXT=OFF MULT=10.00 OUTPUT=BOTH
            AX NOMINAL +TOL -TOL MEAS DEV OUTTOL
            X 0.0000 0.0000 0.0000 -0.0001 -0.0001 0.0001
            Y 0.0000 0.0000 0.0000 -0.1021 -0.1021 0.1021
            D 5.4683 0.0000 0.0000 5.4683 0.0000 0.0000
            END OF DIMENSION D3
            DIM D4= LOCATION OF CIRCLE CIR2 UNITS=IN ,$
            GRAPH=OFF TEXT=OFF MULT=10.00 OUTPUT=BOTH
            AX NOMINAL +TOL -TOL MEAS DEV OUTTOL
            X 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
            Y 0.0000 0.0000 0.0000 -0.1023 -0.1023 0.1023
            D 5.6589 0.0000 0.0000 5.6589 0.0000 0.0000
            END OF DIMENSION D4
            MOVE/INCREMENT,0,6,0
            TIP/T1A90B0, SHANKIJK=-0.0004, 0.0001, -1, ANGLE=-180
            MOVE/POINT,NORMAL,-2.3,5.1,-10.4
            DAT_B_POINT =AUTO/VECTOR POINT,SHOWALLPARAMS = YES
            THEO/-1.85,1.61,-10,0,0,-1
            ACTL/-1.8502,1.6101,-10.0005,0,0,-1
            TARG/-1.85,1.61,-10,0,0,-1
            THEO_THICKNESS = 0,RECT,SNAP = NO,$
            AUTO MOVE = NO,DISTANCE = 0
            B_ORIGIN =ALIGNMENT/START,RECALLAT_A_LINE_LEVEL_AND_ORIGIN, LIST= YES
            ALIGNMENT/TRANS,ZAXIS,DAT_B_POINT
            ALIGNMENT/END
            CLEARP/ZPLUS,-0.2,YMINUS,0
            PREHIT/ 0.3
            RETRACT/ 0.3
            MOVE/CLEARPLANE
            DATUM_Z_1 =AUTO/CIRCLE,SHOWALLPARAMS = YES,SHOWHITS = NO
            THEO/0,0,0.5,0,0,-1,5.47,0
            ACTL/-0.0001,-0.1023,0.5,0,0,-1,5.4688,0
            TARG/0,0,0.5,0,0,-1
            THEO_THICKNESS = 0,RECT,OUT,CIRCULAR,MIN_CIRCSC,ONERROR = NO,$
            AUTO MOVE = NO,DISTANCE = 0,RMEAS = None,None,None,$
            READ POS = NO,FIND HOLE = NO,REMEASURE = NO,$
            NUMHITS = 21,INIT = 0,PERM = 0,SPACER = 0,PITCH = 0,$
            START ANG = 0,END ANG = 360,DEPTH = 0,$
            ANGLE VEC = -1,0,0
            MOVE/CLEARPLANE
            DATUM_Z_TEST =AUTO/CIRCLE,SHOWALLPARAMS = YES,SHOWHITS = NO
            THEO/0,0,0.5,0,0,-1,5.47,0
            ACTL/-0.0003,-0.1021,0.5,0,0,-1,5.4682,0
            TARG/0,0,0.5,0,0,-1
            THEO_THICKNESS = 0,RECT,OUT,CIRCULAR,LEAST_SQR,ONERROR = NO,$
            AUTO MOVE = NO,DISTANCE = 0,RMEAS = None,None,None,$
            READ POS = NO,FIND HOLE = NO,REMEASURE = NO,$
            NUMHITS = 21,INIT = 0,PERM = 0,SPACER = 0,PITCH = 0,$
            START ANG = 0,END ANG = 360,DEPTH = 0,$
            ANGLE VEC = -1,0,0
            sigpic"Hated by Many, Loved by Few" _ A.B. - Stone brewery

            Comment


            • #7
              I added the extra dimensions for cir1 and cir2 trying to figure out WTF.
              sigpic"Hated by Many, Loved by Few" _ A.B. - Stone brewery

              Comment


              • #8
                I am loosing my mind! I copied, pasted and hit submit, somehow there is a smilie stuck in the middle of my code!!! It must be whiskey thirty.
                sigpic"Hated by Many, Loved by Few" _ A.B. - Stone brewery

                Comment


                • #9
                  [ATTACH]1739[/ATTACH]
                  Last edited by John Riggins; 09-28-2007, 06:50 PM.
                  Lately, it occurs to me
                  What a long, strange trip it's been.

                  2017 R1 (Offline programming)

                  Comment


                  • #10
                    Originally posted by John Riggins View Post
                    [ATTACH]1739[/ATTACH]

                    attached is what your link pulls up for me
                    Attached Files
                    sigpic"Hated by Many, Loved by Few" _ A.B. - Stone brewery

                    Comment


                    • #11
                      Originally posted by Wes Cisco View Post
                      I have a horrible part. Crazy design, very tight tolerances, hard to manufacture, hard to measure, etc. After several phone conversations with the customer's CMM programer I finally took a part he had reject to his place with me this morning. The idea was to watch him run it on his Sheffield with MeasureMax and go step by step to figure out why I am getting a measurement .0007 different from what he gets. This is one axis of a .002" trueposition callout. So he tells me that when capturing datums per ANSI Y14.5 etc that I should use Minimum Circumscirbed and Max Inscribed instead of least squared. I thought about it for a minute or two and agreed with the logic. So I come back to my place and try to make my program as identical to his as possible. I measure a circle on one end of the part. (cylinder in v-block). Then I measure a circle on the other end. Create a 3d line between them. Level and origin on the line. I have done this hundreds of times and never a problem. A couple more hits to finish up and create my manual alignment. Then I go back and measure those same two diameters DCC with Minimum Circubscribed and I get the location off by .1" in Z. WTF I tried Max Inscribed and it does not do this. Someone please show the me the stupid thing I am overlooking.

                      Wes,
                      This is not going to help but I can feel your pain. I had an intermittent problem very similar. I could measure a circle manually and in DCC and get two diff centers (about 2mm diff). I icked and I cussed and I scratched me head. I shut down and restarted and it was THERE no matter what. I do not know how or why it went away but when the 2nd shift guy showed up I shut down and he logged on. We checked and the problem was not there. So, I deleted my personal settings filed and wrote his over mine. The next day when I showed up the problem was gone. You will not get me to say that changing the setings file corrected the problem. I do not think this is the case. But . . . .
                      Bill Jarrells
                      A lie can travel half way around the world while the truth is putting on its shoes. - Mark Twain

                      Comment


                      • #12
                        Shorten your probe length if you don't need it.
                        sigpic GDTPS - 0584

                        Comment


                        • #13
                          Code:
                          DATUM_A_1 =AUTO/CIRCLE,SHOWALLPARAMS = YES,SHOWHITS = NO
                          THEO/0,0,-2.26,0,0,1,5.66,0
                          ACTL/0,0.1023,-2.26,0,0,1,5.6551,0
                          TARG/0,0,-2.26,0,0,1
                          THEO_THICKNESS = 0,RECT,OUT,CIRCULAR,MIN_CIRCSC,ONERROR = NO,$
                          AUTO MOVE = NO,DISTANCE = 0,RMEAS = None,None,None,$
                          READ POS = NO,FIND HOLE = NO,REMEASURE = NO,$
                          NUMHITS = 17,INIT = 0,PERM = 0,SPACER = 0,PITCH = 0,$
                          START ANG = 0,END ANG = 180,DEPTH = 0,$
                          ANGLE VEC = 1,0,0
                          MOVE/POINT,NORMAL,-3,0,-3.06
                          DATUM_A_2 =AUTO/CIRCLE,SHOWALLPARAMS = YES,SHOWHITS = NO
                          THEO/0,0,-3.06,0,0,1,5.66,0
                          ACTL/0,0.1023,-3.06,0,0,1,5.6553,0
                          TARG/0,0,-3.06,0,0,1
                          THEO_THICKNESS = 0,RECT,OUT,CIRCULAR,MIN_CIRCSC,ONERROR = NO,$
                          AUTO MOVE = NO,DISTANCE = 0,RMEAS = None,None,None,$
                          READ POS = NO,FIND HOLE = NO,REMEASURE = NO,$
                          NUMHITS = 17,INIT = 0,PERM = 0,SPACER = 0,PITCH = 0,$
                          START ANG = 180,END ANG = 0,DEPTH = 0,$
                          ANGLE VEC = 1,0,0
                          DATUM_A_LINE=FEAT/LINE,RECT,UNBND
                          THEO/0,0,-2.26,0,0,-1
                          ACTL/0,0.1023,-2.26,0.0000223,-0.0000379,-1
                          CONSTR/LINE,BF,3D,DATUM_A_1,DATUM_A_2,,
                          OUTLIER_REMOVAL/OFF,3
                          FILTER/OFF,WAVELENGTH=0
                          Try to figure out why everything red above is off by 0.1023.
                          sigpic GDTPS - 0584

                          Comment


                          • #14
                            Code:
                             
                            DATUM_Z_1 =AUTO/CIRCLE,SHOWALLPARAMS = YES,SHOWHITS = NO
                            THEO/0,0,0.5,0,0,-1,5.47,0
                            ACTL/-0.0001,-0.1023,0.5,0,0,-1,5.4688,0
                            TARG/0,0,0.5,0,0,-1
                            THEO_THICKNESS = 0,RECT,OUT,CIRCULAR,MIN_CIRCSC,ONERROR = NO,$
                            AUTO MOVE = NO,DISTANCE = 0,RMEAS = None,None,None,$
                            READ POS = NO,FIND HOLE = NO,REMEASURE = NO,$
                            NUMHITS = 21,INIT = 0,PERM = 0,SPACER = 0,PITCH = 0,$
                            START ANG = 0,END ANG = 360,DEPTH = 0,$
                            ANGLE VEC = -1,0,0
                            MOVE/CLEARPLANE
                            DATUM_Z_TEST =AUTO/CIRCLE,SHOWALLPARAMS = YES,SHOWHITS = NO
                            THEO/0,0,0.5,0,0,-1,5.47,0
                            ACTL/-0.0003,-0.1021,0.5,0,0,-1,5.4682,0
                            TARG/0,0,0.5,0,0,-1
                            THEO_THICKNESS = 0,RECT,OUT,CIRCULAR,LEAST_SQR,ONERROR = NO,$
                            AUTO MOVE = NO,DISTANCE = 0,RMEAS = None,None,None,$
                            READ POS = NO,FIND HOLE = NO,REMEASURE = NO,$
                            NUMHITS = 21,INIT = 0,PERM = 0,SPACER = 0,PITCH = 0,$
                            START ANG = 0,END ANG = 360,DEPTH = 0,$
                            ANGLE VEC = -1,0,
                            Here too but now negative
                            sigpic GDTPS - 0584

                            Comment


                            • #15
                              I think you were on the right track earlier.
                              It IS whiskey thirty!
                              Lately, it occurs to me
                              What a long, strange trip it's been.

                              2017 R1 (Offline programming)

                              Comment

                              Related Topics

                              Collapse

                              • MatttFlorer
                                Hole diameters
                                by MatttFlorer
                                This may sound dumb, but I'm trying to explain to my manager, whom has no experience with CMM's, how a diameter is created. He seems to think, that when...
                                06-25-2019, 01:39 PM
                              • PCFreddie
                                Oval circle?
                                by PCFreddie
                                I have a circle that may be somewhat oval but I am not sure. I measure it as a circle and it is within spec but the mating part, which measures OK, does...
                                11-24-2010, 12:14 PM
                              • keego
                                Max Inscribed - Again
                                by keego
                                Shouldn't the form of a Max Inscribed circle be perfect? If not, why? We discussed this before and I thought we came to the conclusion that a Max Inscribed...
                                08-05-2009, 02:22 PM
                              • WolfMan
                                Fitting algorithms
                                by WolfMan
                                I have stumbled upon a Min and Max tsebashev fit algorithm for a circle. Based on the help file : minmax - the circle is fitted halfway between two circles,...
                                05-15-2019, 12:56 PM
                              • N3WPV
                                Min/Max for diameter...what is it?
                                by N3WPV
                                If I report a diameter and have the Min/Max option turned on what exactly is that telling me? Is it looking a two opposing points and reporting the min...
                                05-29-2013, 08:45 AM
                              Working...
                              X