Datum C - Cylinder
Datum D - Cylinder
The Position callout that I am interested in is the Position of the left side hole to [C(M)|D(M)] shown at the bottom left of the image.
Datum D has a straightness callout referenced at MMC.
Datum C has a Position callout at MMC to [D(M)]
The boundary size at MMB of datum feature C for DRF [C(M)|D(M)] is just a cylinder at the MMC size of C.
The boundary size at MMB of datum feature D for DRF [C(M)|D(M)] is unclear to me.
Per Y14.5-2009 4.11.6.1 I must calculate the MMB as the size at MMC plus any applicable geometric tolerance to the higher precedence datum so as to not violate datum precedence. In this case, there is no control on D with respect to C. All I have is the straightness tolerance on D, but that callout does not reference C as primary (i.e. it is not necessarily applicable while constrained to C.)
My question is: Do I reference datum D at a custom boundary size which is (Size at MMC + Straightness Tolerance)? Or do I reference it as is seen on the drawing?
I am thinking of measuring to [C(M)|D(M)[Ø.XXX]] where .XXX is (Size at MMC + Straightness).
STRAIGHTNESS.jpg
Datum D - Cylinder
The Position callout that I am interested in is the Position of the left side hole to [C(M)|D(M)] shown at the bottom left of the image.
Datum D has a straightness callout referenced at MMC.
Datum C has a Position callout at MMC to [D(M)]
The boundary size at MMB of datum feature C for DRF [C(M)|D(M)] is just a cylinder at the MMC size of C.
The boundary size at MMB of datum feature D for DRF [C(M)|D(M)] is unclear to me.
Per Y14.5-2009 4.11.6.1 I must calculate the MMB as the size at MMC plus any applicable geometric tolerance to the higher precedence datum so as to not violate datum precedence. In this case, there is no control on D with respect to C. All I have is the straightness tolerance on D, but that callout does not reference C as primary (i.e. it is not necessarily applicable while constrained to C.)
My question is: Do I reference datum D at a custom boundary size which is (Size at MMC + Straightness Tolerance)? Or do I reference it as is seen on the drawing?
I am thinking of measuring to [C(M)|D(M)[Ø.XXX]] where .XXX is (Size at MMC + Straightness).
STRAIGHTNESS.jpg
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