Position on Keys

[[Ad...]]

I have a position on the two keys with an angle of 21 and 32 degrees. Now they have to be positioned to Datum's -A- and -B-. Datum -A- is a Circle and Datum-B- is on of the Keys at size .1051 to .1057. Here is my question when I input the the Datum's -A- and -B-, I use a theoretical Circle for Datum -B- in order to use MMB but the two keys would measure out of position. But when I change the theoretical circle to symmetry they would measure in position. I would like to know how is the Calypso calculating difference between using a theoretical circle as a Datum, and using Symmetry as a Datum?


Thanks

Position.png

[[SH...]]

In calypso circle is two dimensional concept and plane is three dimensional concept, that might be the reason also you have to use cylinder as primary datum.

[[Gr...]]

I have provided an attachment from Zeiss has to how to help with the true position of a slot.
Hope this helps

Greg

[[Ad...]]

Okay, this make sense but is there a difference when using a circle or cylinder for Datum -A-? Because the diameter is not enough to create a cylinder.

[[Gr...]]

Did not see what features are the datum.
I would use a face for spatial, the thru bore for center, datum A ? would be a circle for planar clocking.
Create a secondary alignment (Resources>Utilities) and reference it for your measured slots.
I have used symmetry plan but I get more stable results using the protocol I posted.