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Can datum creation in assembly mode relate to part dimension


New member
View attachment 102

Kind of tough to tell from the JPEG but what I have are two datums that define the centerline of the card guide and the bottom surface of the guide channel (DTM1 & DTM2).

To place DTM1 on the centerline I used an offset plane and the value of the offset is a relation based on half the sketch dimension controlling the slot width.

Is there a way to maintain this relation but have the datum created at the assembly level? This would make layer control easier and eliminate the datums being recreated every fourth slot (width of the protrusion).

If it makes any difference the part is a member of a family table. It's likely that the assembly will also become a family table. If I had the Advanced Assembly module I wouldn't have to resort to this but I want to be able to take advantage of replace by family member on future versions of the cardcage.

Bernie Hayden



New member
I think this should be possible, I know that when writing relations in an assembly, you use Part Id in the relation.

As long as the Part Id does not change when doing a replace by Fam Table your relations should stay good.



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