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Equate alignment (FrogLeap)

Hello.

I have a part that is longer than my CMM.
So, I’m into FrogLeaping, but also into a “wall”.


Here is my procedure, with focus on my alignments.

STARTUP =ALIGNMENT/START,RECALL:USE_PART_SETUP,LIST=YES

I do a manual iterate alignment, to “tell” the CMM where the part is. This alignment is called “A_MAN_PART”.
A_MAN =ALIGNMENT/START,RECALL:STARTUP,LIST=YES

After is the CMM does an alignment in DCC-mode. This alignment is called “A_OP_PART”.
A_OP_PART =ALIGNMENT/START,RECALL:A_MAN,LIST=YES

Now I measure all the points and circles on the first half of the part, according to the requirement on the drawing.
This part of the program with all features from first half of the part, ends with measuring the features (5 points and a circle), that I am going to re-measure after I have moved the part on its fixture.
Those features are given a name that ends with “_BEFORE”.
Then I do an alignment, using those “_BEFORE”-features. This alignment is called “A_BEFORE”.
A_BEFORE =ALIGNMENT/START,RECALL:A_OP_PART,LIST=YES

I move the part the distance, which is needed, for measuring the second half. In this case it is 780 mm.
No rotation or anything else, the part is moved parallel to the machine-axis.

I repeat taking the “_BEFORE”-point but of course in the new position. 780 mm away from pervious.
Those points are called a name that ends with “_AFTER”.
And the next alignment is made and called “A_AFTER”.
A_AFTER =ALIGNMENT/START,RECALL:A_OP_PART,LIST=YES

I now have what I need for doing the FrogLeap.
EQUATE/A_AFTER, TO ALIGNMENT, A_BEFORE

Then I recall my “original” alignment of the part
RECALL/ALIGNMENT,INTERNAL,A_OP_PART

With that in place, I continue taking points, and circles on the second half of the part.
With all that done, I have all the features (points and circles) needs for completing the report.
I this specific case, my customer has placed his alignment points on both half’s of the part.
This is processed in the next alignment. It is a iterate alignment, that I named “A_OP_UTV” looking like this.
A_OP_UTV =ALIGNMENT/START,RECALL:A_OP_PART,LIST=YES

With all this in place, I now generate my report.


When I execute the program again for measuring the next part, the coordinates for my manual alignment are moved according to the FrogLeap.
In other words, they are not in the same place as when I began. They are moved 780 mm.

So, my question and challenge is:
HOW DO I GET IT BACK TO WHERE I STARTED?

I have temporarily solved this “mishap” by forcing the operator to re-take the manually points every time the program is executed.
I was thinking that an external alignment, loaded into the program at the beginning also could be a solution, but I both cases I don’t think that it’s the way it’s supposed to be done.
I even tried to do a “reversed” FrogLeaping, but I couldn’t pick the alignments in the reversed order. So that wasn’t an option for me.

What am I missed?
What have I done wrong?


Please help me, because I can‘t see the error.

Best regards

Michael Larsen - DEA15-09-08 - PC-DMIS 2019 R1