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Legacy dimension - profile of a surface

First of all, I am aware this topic has been covered, but my google-fu failed to find a solution for my current conundrum.

All that follows is relative to PC-DMIS 2012

Part setup:
Datum A: Cylinder along Z, locking X, Y and two rotational DoF
Datum B: Plane perpendicular to A, locking Z
Datum C: Plane perpendicular to B at 5.5 basic from A's axis, locking the last rotational DoF

Callout:
Profile of a surface of datum C relative to datum A

The issue:
While this is pretty straightforward to do with exact dimensions, the report template at my current workplace plays nicely only with legacy dimensions.
The result of legacy profile of a surface (form and position, LSQ best fit) while aligned to ABC are different (worse) than exact above.
To my understanding this is to be expected as legacy "form and location" fits to the current alignment, which is restricting 6 DoF instead of just 4 as Datum A alone would.
If this is the case, is there any way to use legacy with the callout that I have?
Parents
  • Changing UseSizeForProfileDimensions causes the dimension to change if the best fit is done with a set or individual points, but no difference if the plane is used. None of the results corresponds to Xact.

    Regarding VinniUSMC's suggestion, using the individual points causes yet another change in the result, but it still does not align with Xact.

    My issue is that I have several sets of values (Xact, Legacy with various different settings combination for the alignment's best fit) that should be substantially equivalent but show rather large differences (up to 0.015mm on a small sample size, so larger discrepancies would not surprise me on bigger data sets) and I have no idea which one to trust.
Reply
  • Changing UseSizeForProfileDimensions causes the dimension to change if the best fit is done with a set or individual points, but no difference if the plane is used. None of the results corresponds to Xact.

    Regarding VinniUSMC's suggestion, using the individual points causes yet another change in the result, but it still does not align with Xact.

    My issue is that I have several sets of values (Xact, Legacy with various different settings combination for the alignment's best fit) that should be substantially equivalent but show rather large differences (up to 0.015mm on a small sample size, so larger discrepancies would not surprise me on bigger data sets) and I have no idea which one to trust.
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