Datum Target in Base Alignment

[[To...]]

Per the sketch below, I'm looking for confirmation as to the proper type of point to use for datum target C. In the attachment, I show the affects of using Touch, Space and Plane points in the Base Alignment. I'm leaning towards using a space point though I feel a plane point is the proper way. Anyway, I welcome your thoughts.

Note: the sketch shows the datum point surface to be perpendicular to Datum B but in the attachments, you will see that there is a slight angle (~2.5°)
.
.

Datum Target C screenshots.pdf

[[Ri...]]

I don't think you are going to see much of a difference using the Space Point vs the Plane Point.

When doing 3-2-1, or 3d Best Fit Alignments, I just tend to use Plane Points as the software will ask you to use them (for the 3d Best Fit).

[[To...]]

Part 2 - There are several position call-outs of holes to A, B w/MMB and C. The MMB option is not available on the Symmetry Plane, even with View Tolerance (with MMC/LMC of the references) active. Any thoughts on a work-around to allow for datum shift

[[Ri...]]

Please sign in to view this quote.

Hopefully this will be added in future releases, but it is currently not possible in Calypso.

[[Er...]]

I use the base alignment to find the part. Using datum targets is nice, but getting a solid lock onto the part is my priority. Using a calculated or constructed feature, like a symmetry plane, has led to grief in the middle of a capability run when Calypso pops up a "can't calculate alignment" due to part variability. 😮

In this case I'd make a base alignment that is made of features I already have to measure. Then I'd use an Alignment using -A- and -B- to find -C-. If I wanted to be sure -ABC- was locked in I could then make a conditional loop on an -ABC- alignment.