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.
H E L P ! ! ! Please!
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Originally posted by John Riggins View Post
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
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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 = -1,0,0sigpic"Hated by Many, Loved by Few" _ A.B. - Stone brewery
Comment
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[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
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Originally posted by Wes Cisco View PostI 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
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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
sigpic GDTPS - 0584
Comment
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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,
sigpic GDTPS - 0584
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