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Manual vs DCC alignment

I have taken the basic 1 week PCDMIS course from Hexagon.

Currently I have only modified part programs written by the programmer at our parent company location to run on our cmms.

I work with version 3.7 on cmm 2 and 2014 on cmm 3.

Cmm 1 has Measuremax which I am not sure how to program. This question is regarding cmm 2.

I think I may be a little confused about the purpose of running the dcc alignment after the manual alignment has run. I was under the impression that the manual alignment was to locate the part on the cmm, and the dcc alignment was the "fine tuning" and would adjust for very slight placement changes.

We have a fixture that is bolted to the fixture plate. The part is then mounted on the fixture and screwed into place using 1 screw. The part is secure, but due to different cavities with different die conditions may sit slightly different in the fixture each time. We are measuring the true position of a bore on the x minus side of the part with respect to the plane and bore at the x/y/z 0 position that is used to set the part alignment.

What we have noticed is that when we run the first part with the manual alignment the true position is within tolerance (.04mm). When we run a second part, if I mark all but choose not to mark the manual alignment portion, we see true position values between 0.1mm and 0.2mm.

If I then run the program on that same part again using the manual alignment without moving the part the true position values are again within tolerance. From what I read online yesterday after lots of digging it looks like the dcc alignment serves only to ensure the alignment features are properly probed and defined.

Is there any way around running the manual alignment each time? I don't mind if it's necessary for different cavities or runs, but for a 300pc cpk it's quite time consuming. Thanks in advance for any answers and/or suggestions. Oh, and I'm well aware of the noob hazing here. I have thick skin Slight smile.

Amber
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  • Not when using Auto circles surely?


    In my 20+ years of Pcdmis, auto-feature circles do NOT require a workplane since the feature itself HAS a 'workplane' built in, with the vectors. Workplane is required for a learned circle, not for an autofeature circle. The autofeature circle does require the correct vector, which will come from the CAD or correctly typed in by the operator. If the autofeature circle does NOT have the correct vector, then workplane will not help it at all. Now, in doing 'auto dimensions', the workplane may have an effect of what is reported (as in, which axis it selects) but not in correct XYZ values themselves.
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  • Not when using Auto circles surely?


    In my 20+ years of Pcdmis, auto-feature circles do NOT require a workplane since the feature itself HAS a 'workplane' built in, with the vectors. Workplane is required for a learned circle, not for an autofeature circle. The autofeature circle does require the correct vector, which will come from the CAD or correctly typed in by the operator. If the autofeature circle does NOT have the correct vector, then workplane will not help it at all. Now, in doing 'auto dimensions', the workplane may have an effect of what is reported (as in, which axis it selects) but not in correct XYZ values themselves.
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