Readpoint alignments are simple. Set your point at XYZ 0, translate XYZ to that point and your off. That being said, I want to keep my trihedron in the same spot and there is typically no feature at the trihedron that I can use. I will use the closest hole to the trihedron then offset the alignment. In this program I also have 2 points that I use to rotate to. I do this for select parts that do not have a mounting feature parallel/perpendicular to an axis or on longer parts. In this case, the bottom surface is not true to the granite.
In the second example I use dual start point. This is a longer part so I do a readpoint in the datum b circle, another one in the datum c circle, rotate to the two readpoints, then translate to one of them. This is one of the first programs I did this with and I constructed a line between the two readpoints to rotate to. This is unnecessary, you can rotate to the two features paying attention to the order in which the features are selected when doing the rotate in the alignment dialogue box and selection a rotation direction accordingly. Rotating without a constructed line is what I do now. The other thing I do now is run two start circles, rotate between them both, then translate to one of them.
START_PNT =FEAT/POINT,CARTESIAN THEO/<[COLOR=#e74c3c]0.875,0.5,-0.5[/COLOR]>,<0,0,1> ACTL/<16.3163,14.5666,-25.6181>,<0,0,1> READPOINT/ START_PNT_ALN=ALIGNMENT/START,RECALL:STARTUP,LIST=YES ALIGNMENT/TRANS,XAXIS,START_PNT [COLOR=#e74c3c]ALIGNMENT/TRANS_OFFSET,XAXIS,-0.875[/COLOR] ALIGNMENT/TRANS,YAXIS,START_PNT [COLOR=#e74c3c]ALIGNMENT/TRANS_OFFSET,YAXIS,-0.5[/COLOR] ALIGNMENT/TRANS,ZAXIS,START_PNT [COLOR=#e74c3c]ALIGNMENT/TRANS_OFFSET,ZAXIS,0.5[/COLOR] ALIGNMENT/END CLEARP/XPLUS,2.5,XPLUS,0,OFF MOVE/CLEARPLANE START_CIR =FEAT/CONTACT/CIRCLE/DEFAULT,CARTESIAN,IN,LEAST_SQR THEO/<0.875,0.5,-0.5>,<1,0,0>,0.379 ACTL/<0.8773,0.5057,-0.5167>,<0.999983,0.0050583,0.0028966>,0.3801 TARG/<0.875,0.5,-0.5>,<1,0,0> START ANG=0,END ANG=360 ANGLE VEC=<0,0,-1> DIRECTION=CCW SHOW FEATURE PARAMETERS=NO SHOW CONTACT PARAMETERS=YES NUMHITS=6,DEPTH=0.03,PITCH=0 SAMPLE METHOD=SAMPLE_HITS SAMPLE HITS=3,SPACER=0.1 AVOIDANCE MOVE=BOTH,DISTANCE=0.2 FIND HOLE=DISABLED,ONERROR=NO,READ POS=NO SHOW HITS=NO MOVE/CLEARPLANE [COLOR=#e74c3c]SR1 =FEAT/CONTACT/VECTOR POINT/DEFAULT,CARTESIAN[/COLOR] THEO/<0.75,0,-0.0892>,<0,-1,0> ACTL/<0.75,-0.0165,-0.0892>,<0,-1,0> TARG/<0.75,0,-0.0892>,<0,-1,0> SNAP=NO SHOW FEATURE PARAMETERS=NO SHOW CONTACT PARAMETERS=YES AVOIDANCE MOVE=NO,DISTANCE=0.2 SHOW HITS=NO [COLOR=#e74c3c]SR2 =FEAT/CONTACT/VECTOR POINT/DEFAULT,CARTESIAN[/COLOR] THEO/<0.75,0,-1.5239>,<0,-1,0> ACTL/<0.75,0.0639,-1.524>,<0,-1,0> TARG/<0.75,0,-1.5239>,<0,-1,0> SNAP=NO SHOW FEATURE PARAMETERS=NO SHOW CONTACT PARAMETERS=YES AVOIDANCE MOVE=NO,DISTANCE=0.2 SHOW HITS=NO START_CIR_ALN=ALIGNMENT/START,RECALL:START_PNT_ALN,LIST=YES ALIGNMENT/LEVEL,XPLUS,START_CIR [COLOR=#e74c3c]ALIGNMENT/ROTATE_CIRCLE,ZMINUS,TO,SR1,AND,SR2,ABOUT,XPLUS[/COLOR] ALIGNMENT/TRANS,XAXIS,START_CIR ALIGNMENT/TRANS_OFFSET,XAXIS,-0.875 ALIGNMENT/TRANS,YAXIS,START_CIR ALIGNMENT/TRANS_OFFSET,YAXIS,-0.5 ALIGNMENT/TRANS,ZAXIS,START_CIR ALIGNMENT/TRANS_OFFSET,ZAXIS,0.5 ALIGNMENT/END
COMMENT/OPER,NO,FULL SCREEN=NO,AUTO-CONTINUE=NO, TWO START POINT PROGRAM. PARK PROBE AT FIRST READ POINT (CENTER OF DATUM B CIRCLE). SELECT "OK" TO CONTINUE TO SECOND START POINT. [COLOR=#e74c3c]START_POINT_1=FEAT/POINT,CARTESIAN[/COLOR] THEO/<0,0,0>,<0,0,1> ACTL/<0.4513,-42.9844,-0.7738>,<0,0,1> READPOINT/ COMMENT/OPER,NO,FULL SCREEN=NO,AUTO-CONTINUE=NO, PARK PROBE AT SECOND READ POINT (CENTER OF DATUM C CIRCLE). SELECT "OK" TO ENTER DCC MODE. [COLOR=#e74c3c]START_POINT_2=FEAT/POINT,CARTESIAN[/COLOR] THEO/<0,-36.1,0>,<0,0,1> ACTL/<0.4513,-42.9844,-0.7738>,<0,0,1> READPOINT/ [COLOR=#e74c3c]START_LINE =FEAT/LINE,CARTESIAN,UNBOUNDED,NO[/COLOR] THEO/<0,0,0>,<0,-1,0> ACTL/<0,0,0>,<0,-1,0> CONSTR/LINE,BF,2D,START_POINT_1,START_POINT_2,, OUTLIER_REMOVAL/OFF,3 FILTER/OFF,WAVELENGTH=0 START_POINT_ALN=ALIGNMENT/START,RECALL:STARTUP,LIST=YES [COLOR=#e74c3c]ALIGNMENT/ROTATE,YMINUS,TO,START_LINE,ABOUT,ZPLUS[/COLOR] ALIGNMENT/TRANS,XAXIS,START_POINT_1 ALIGNMENT/TRANS,YAXIS,START_POINT_1 ALIGNMENT/TRANS,ZAXIS,START_POINT_1 ALIGNMENT/END CLEARP/ZPLUS,2.5,ZPLUS,0,OFF MOVE/CLEARPLANE START_CIR =FEAT/CONTACT/CIRCLE/DEFAULT,CARTESIAN,IN,LEAST_SQR THEO/<0,0,0>,<0,0,1>,0.5 ACTL/<0,0,0>,<0,0,1>,0.5 TARG/<0,0,0>,<0,0,1> START ANG=0,END ANG=-360 ANGLE VEC=<-1,0,0> DIRECTION=CW SHOW FEATURE PARAMETERS=NO SHOW CONTACT PARAMETERS=YES NUMHITS=7,DEPTH=0.04,PITCH=0 SAMPLE METHOD=SAMPLE_HITS SAMPLE HITS=0,SPACER=0.1 AVOIDANCE MOVE=BOTH,DISTANCE=0.2 FIND HOLE=DISABLED,ONERROR=NO,READ POS=NO SHOW HITS=NO START_CIR_ALN=ALIGNMENT/START,RECALL:START_POINT_ALN,LIST=YES ALIGNMENT/TRANS,XAXIS,START_CIR ALIGNMENT/TRANS,YAXIS,START_CIR ALIGNMENT/TRANS,ZAXIS,START_CIR ALIGNMENT/END
