When you reference features as common datums, we recommend you use 3D features for these reasons:
3D features represent feature surface(s) and capture more data to properly evaluate your datums.
3D features properly control the applicable Degrees of Freedom (DOF) which you can then use as primary, secondary, and tertiary datums.
You can only reference 2D and 1D width features as secondary or tertiary datums.
PC-DMIS does not support a pattern of 2D features as part of a common datum. PC-DMIS only allows datum patterns made up of cylinders, spheres, or 3D widths as part of a common datum.
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