ASME Y14.5 DoF two datums

[[Er...]]

I need clarification on a subject and I know there are some really knowledgeable guys and gal's here regarding asme and standards in general.

If you have a plane that's datum A, a diameter that's datum B and a circular hole pattern that's datum C.
And then a second hole pattern, with a true position callout to |A|C|. Does |A|C| lock all degrees of freedom? Meaning both center and clocking are coming from C? I thought you always need three datums to fully constrain all DoF 😮

I'm in an argument with a customer saying it's fully constrained. But to be honest, I'm not shure anymore after the meeting we just had.

They are shoving Page 69, Fig. 4-26. in my face.

[[To...]]

I'm not quoting any standard but I would assume since C is a pattern of holes, it probably does restrict all degrees of freedom.

[[Ra...]]

Y14.5-2009 4.12.3 is the applicable section, I believe. Paraphrasing: the pattern creates the second and third planes of the DRF. So as I read it, yes - pattern restricts translation/rotation not already controlled by primary.

[[Er...]]

Thanks you guys for your replies.

Guess it's time for me to read all the pages.. I just wished we could stick to ISO1101. No, now we have BS8888, ASME, JES170 and god know the name of all of them..
One more reason to hate international trading =)

[[Aa...]]

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At least with ASME Y14.5, you're talking about reading all the pages. With ISO, the first order of business is finding all the pages. 1101 is only the beginning. You also need 1660, 2692, 5458, 5459, 8015, 12180, 12181, 12780, 12781, and 14660. The question you presented in this thread, for example, isn't answered in 1101. (I believe that answer would be found in 5459.)

[[Er...]]

impeccable systematic organized