First of all, I'm coming in behind someone who already setup about a dozen programs using two different fixtures. For the sake of continuity, I followed their lead. Here is the situation:
There are two fixtures that check about a dozen or so parts. An separate alignment program was written to rough locate the fixtures on the plate. Basically two threaded holes in the fixture plate and a surface point on the plate.
Next, these rough alignments are recalled into part programs as external alignments. Next, the guy just open up the auto features window and sampled features on the part itself, not any features off the fixture. There is no correlation between the external alignment and the auto features that are developed off of it, and the part nominals. The features are simply measured to what ever alignment was created off the external alignment program. When sampling part features with the external alignment, the machine is in DCC, so basically you end up with a DCC program that samples features and then creates a part alignment.
Now the problems begin. After creating a part alignment, I brought in a part CAD file and did a CAD = Part. I wrote a program for the part using the CAD model without any problems. When I tried to run the program from the beginning however, the nominals for the DCC alignment features changed. I believe this was a result of the CAD = Part command. Furthermore, after resampling the DCC alignment features to the external alignment again, I found that the rest of the features are no longer linked to the CAD file and now they want to check out in space somewhere.
In the past, I have always written these automatic alignment files in a separate program and then called that external alignment into the part program. So basically, you would have a manual alignment program that would locate the fixture on the plate, a separate DCC alignment program off of that fixture or the part and finally a part program that recalled the external DCC alignment. This way, if the fixture didn't move on the plate, you would just run the auto alignment and go.
What am I doing wrong here? Is there something going on with this external alignment? The DCC alignment inside the program (with nominals that don't relate to anything except to rough fixture alignment to the plate) or is there something going on with the CAD = Part command? It looks like all of the programs that were written previously used the method described and in fact, I was able to write a program with this method until my problems tonight.
Also, why is CAD = Part sometimes in the Alignment menu and other times, it is not? Am I pulling the CAD into the program at the wrong time? Any help with this would be appreciated. I am completely flummoxed with this **** thing!
There are two fixtures that check about a dozen or so parts. An separate alignment program was written to rough locate the fixtures on the plate. Basically two threaded holes in the fixture plate and a surface point on the plate.
Next, these rough alignments are recalled into part programs as external alignments. Next, the guy just open up the auto features window and sampled features on the part itself, not any features off the fixture. There is no correlation between the external alignment and the auto features that are developed off of it, and the part nominals. The features are simply measured to what ever alignment was created off the external alignment program. When sampling part features with the external alignment, the machine is in DCC, so basically you end up with a DCC program that samples features and then creates a part alignment.
Now the problems begin. After creating a part alignment, I brought in a part CAD file and did a CAD = Part. I wrote a program for the part using the CAD model without any problems. When I tried to run the program from the beginning however, the nominals for the DCC alignment features changed. I believe this was a result of the CAD = Part command. Furthermore, after resampling the DCC alignment features to the external alignment again, I found that the rest of the features are no longer linked to the CAD file and now they want to check out in space somewhere.
In the past, I have always written these automatic alignment files in a separate program and then called that external alignment into the part program. So basically, you would have a manual alignment program that would locate the fixture on the plate, a separate DCC alignment program off of that fixture or the part and finally a part program that recalled the external DCC alignment. This way, if the fixture didn't move on the plate, you would just run the auto alignment and go.
What am I doing wrong here? Is there something going on with this external alignment? The DCC alignment inside the program (with nominals that don't relate to anything except to rough fixture alignment to the plate) or is there something going on with the CAD = Part command? It looks like all of the programs that were written previously used the method described and in fact, I was able to write a program with this method until my problems tonight.
Also, why is CAD = Part sometimes in the Alignment menu and other times, it is not? Am I pulling the CAD into the program at the wrong time? Any help with this would be appreciated. I am completely flummoxed with this **** thing!
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