Confounding Composite Position

[[Ke...]]

For the image, below:
Datum E is a Cylindrical feature
Datum F is a Hole Diameter
Datum A is a Plane
Datum C is a Plane

The first level of the control frame: not much to unpack
The second level of the control frame:
- I'm used to seeing composite control frames where the 2nd level is a refinement of the 1st level (uses the same datums, but fewer)
-Datums A & C are both planes, with the same angles, but on seperate levels... Calyso allows me to use A as Primary, and C as Secondary datums... but my guess would be that Datum C would be ineffective,

Thoughts?
I don't have a physical part, yet...

[[Jo...]]

I don't think that is a legal Composite callout. ASME Y 14.5-2018 10.5.2 is what it "should" be. figure 6-27

[[Ke...]]

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Meaning that it should be split into 2 single segment control frames, yes?

What about the use of A as primary, & C as secondary (presuming that it is called out as a single segment control frame)?
...my best guess is that they want A & C to be used as an offset plane (A-C)

[[Jo...]]

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I think technically it has to be single segment control frame to allow different Datums. I'm not even going to venture a guess concerning design intent.

[[Ro...]]

Hi Keith,

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Yes

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The way it is now, -C- does nothing because -A- is already constraining 2 rotational and 1 translational per the Can/May/Must rule. If they wanted an offset plane then they would be co-datums A-C in the FCF as you stated. Or they would need to release degrees of freedom in -A- and assign them to -C- in the FCF.