Profile / Constraint

[[Cl...]]

I have a cylindrical part laying along the X axis. The primary datum (-A-) is the last 2/3rds of the X+ side of the cylinder.
Behind that (X-) is a square feature on the same axis. The print calls out surface profile of the square back to -A- only.
There is no clocking datum involved other than the base alignment. I'm failing the type-1 because of this (I believe).
What would you suggest if anything?

[[Ma...]]

If your base alignment does not stop rotation, then it should work with base alignment. Otherwise make new alignment with only cylinder for center and as main and this should work too ( bestfit rotationaly )
Or you can fill in profile callout all three features for alignment as that cylinder.

[[Cl...]]

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The Base Alignment does stop rotation. As far as using ( bestfit rotationaly ). I was always told that this cannot be used when the profile is called back to a datum, which mine is.

[[Ma...]]

So you can either fill features in profile callout ( like select no alignment, or clicking on that icon to fill that by features ) or you can go to FF and select bestfit with constraint relative to feature alignment.

[[To...]]

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The way I see it, the 4 sides of the square, are allowed to rotate about the Datum A axis, simultaneously. However, a best fit of the 4 planes might be causing you the lack of repeatability. Sounds like a loop on the best fit alignment might be necessary to get it better.

Don't hold me to this, as I am just thinking out loud, but maybe a secondary alignment with Datum A cylinder as Spatial and Y/Z Origin. (I don't know if a secondary alignment is necessary, maybe the BA is ok for the next step) Then, a geometry best fit alignment of the 4 planes, rotating about X, to previous alignment. Then, Profile of a free form surface of 4 planes to Geometry Best Fit alignment. Unfortunately, this suggestion doesn't allow for a loop.

[[Cl...]]

Thanks Tom. I will give your suggestion a try.