I am beginning to attempt to program off a cad model. I have a sample part, every time I press cad=part my alignment moves off my cad model. I am actually trying to program off of cad on a part I have a sample for before I make a program off a part that I have no sample for.
If you insist on using C=P then you need to TRANSLATE your model to match the part orientation as it sits on the table, hence the whole C=P thing.
Nope, not true, not even CLOSE to true. You do NOT ever "need" to translate a model, not for any reason at all.
CAD=PART works, and it works every time. However, if you do NOT make the alignment correct, then using it will do no good at all.
If you have a square block, and the top is A, the front is B, and the left side is C, then you measure a plane on top, measure a line on the front (LEFT to RIGHT), and measure a line on the left side, then construct a point where the 2 lines intersect.
Then you LEVEL (Z+) to the plane, ROTATE (X+) to the line on the front, then set X ORIGIN to the point, Y ORIGIN to the point, Z ORIGIN to the plane.
Now, if that corner is X0Y0Z0, in theory, you are done, you are aligned.
HOWEVER, if the top of that block is Z1.5, then in the alignment you need to OFFSET the Z ORIGIN -1.5 (as in, push the Z0 down 1.5 so that the plane will be +1.5 from the absolute zero).
Same with the X and Y.
Now, do you HAVE to do CAD=PART even then? No, not really BUT!!!!!!!!
When you do the CAD=PART once you have level, rotate, origin, origin-offset), then all those manual features you just measured will now have THEO values and VECTORS that match the ALIGNMENT you just made. If you do NOT do CAD=PART, their theo's and vector will remain in MACHINE CO-ORDINATES. Your plane won't have a Z nominal (THEO) of -127.487 and a vector of .000001, 0.00023, 0.99999, it will have a Z THEO of 1.5 (see above, the origin offset) and it will have a vector of 0,0,1. Every time.
BUT, you, the person creating the alignment, MUST make the alignment correctly. If your cad model of that square block has X123, Y453, Z1.5 at the datum corner, and you do NOT do the ORIGIN OFFSET, but simply set the origins to those features, then do CAD=PART, your features will 'snap' to the X0Y0Z0 absolute relationship to the CAD model.
Even if you have to set the 'block' up so that X+ is UP (machine Z+), and Y+ is LEFT (machine X-) and Z+ is FRONT (machine Y-), you will do not need to translate the model, you can either just do the alignment correctly, and it will be correct once you are on the machine, OR, you can use the F5 PART/MACHINE function. What that does is 'change' the machine axis to match the cad model (part) orientation as you have it on the machine.
Machine axis (XYZ) are not something 'set in stone', they are nothing more than 'starting reference' thingies. X+ does NOT have to point to the right, that is simply a starting 'idea', nothing more, nothing less.
If you insist on using C=P then you need to TRANSLATE your model to match the part orientation as it sits on the table, hence the whole C=P thing.
Nope, not true, not even CLOSE to true. You do NOT ever "need" to translate a model, not for any reason at all.
CAD=PART works, and it works every time. However, if you do NOT make the alignment correct, then using it will do no good at all.
If you have a square block, and the top is A, the front is B, and the left side is C, then you measure a plane on top, measure a line on the front (LEFT to RIGHT), and measure a line on the left side, then construct a point where the 2 lines intersect.
Then you LEVEL (Z+) to the plane, ROTATE (X+) to the line on the front, then set X ORIGIN to the point, Y ORIGIN to the point, Z ORIGIN to the plane.
Now, if that corner is X0Y0Z0, in theory, you are done, you are aligned.
HOWEVER, if the top of that block is Z1.5, then in the alignment you need to OFFSET the Z ORIGIN -1.5 (as in, push the Z0 down 1.5 so that the plane will be +1.5 from the absolute zero).
Same with the X and Y.
Now, do you HAVE to do CAD=PART even then? No, not really BUT!!!!!!!!
When you do the CAD=PART once you have level, rotate, origin, origin-offset), then all those manual features you just measured will now have THEO values and VECTORS that match the ALIGNMENT you just made. If you do NOT do CAD=PART, their theo's and vector will remain in MACHINE CO-ORDINATES. Your plane won't have a Z nominal (THEO) of -127.487 and a vector of .000001, 0.00023, 0.99999, it will have a Z THEO of 1.5 (see above, the origin offset) and it will have a vector of 0,0,1. Every time.
BUT, you, the person creating the alignment, MUST make the alignment correctly. If your cad model of that square block has X123, Y453, Z1.5 at the datum corner, and you do NOT do the ORIGIN OFFSET, but simply set the origins to those features, then do CAD=PART, your features will 'snap' to the X0Y0Z0 absolute relationship to the CAD model.
Even if you have to set the 'block' up so that X+ is UP (machine Z+), and Y+ is LEFT (machine X-) and Z+ is FRONT (machine Y-), you will do not need to translate the model, you can either just do the alignment correctly, and it will be correct once you are on the machine, OR, you can use the F5 PART/MACHINE function. What that does is 'change' the machine axis to match the cad model (part) orientation as you have it on the machine.
Machine axis (XYZ) are not something 'set in stone', they are nothing more than 'starting reference' thingies. X+ does NOT have to point to the right, that is simply a starting 'idea', nothing more, nothing less.
