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Regarding the original question: The idea of the Common Datum Features such as those referenced as A-B or A-B-C is establishment of a single datum from two or more datum features that arrest the same degrees of freedom together. Whether a third coaxial datum feature cylinder should be part of...

For the D,B datum reference frame the true geometric counterpart for 'D' is an expanding cylinder completely independent from anything else, because it's primary. The true geometric counterpart for secondary 'B' is a pair of two parallel planes collapsing on the edge surfaces of the 100 mm...

For handling the interrupted threads and their starts I would expect some kind of functional go-gage implemented, considering the expected quantities and long-term production.

Possibly a component that was hidden by the black portion gets sandwitched and clamped between the blue and green parts, and then there must be gaps maintained between the green and blue cones and between what may be a washer and the end face of the blue part, in the fully tightened condition...

Consider this:

Could you post some rough sketch of the parts in question, how they mate, and what specific geometric relationships between features you want to control to ensure the fit?

It depends on whether the required basic geometry/dimensions are defined. Profile requires a basically dimensioned "true profile" to establish the profile tolerance zone around. The basic dimensions could be given on a drawing or they may be defined by a CAD model, depending on the type of...

Dima, The inspection can be done using a physical measurement fixture and CMM: 1. The measurement fixture: A fixture that includes a flat surface to simulate datum plane A and a fixed-diameter pin attached to it to simulate datum axis B. The pin diameter is 19.6, based on the virtual...

Since you say that the M10 threaded hole is the "fixing attachment," it is the best candidate to be selected as a locating datum feature. It probably should be a secondary datum feature, while the face perpendicular to it, against which the component is clamped by the screw, is proper as the...

I would use straightness: In that example it's shown on a cylinder but the same can be applied to flat surface.

Glass Half Full, To provide different position tolerance values in different directions you can use this method per ISO 1101-2017: Or this former practice that is also still allowed in ISO 1101-2017:

Following up on what pmarc said, I would add the clarification that while the datum features that were specified are functional for assembling and positioning parts on the component in question, there are certainly features intended to assemble and position the component onto the machine itself...

The width and height of the features in the pattern need to be TED-defined (to define the theoretically exact profiles of the features), the centers are implied to be centered to the TED-profiles because, well, they are centers (represented by center lines). So, no edge-to-center TED dims are...

The problem is not with dimensioning the centers by TEDs but with the profile surface tolerance applied to the centers of recesses. Surface profile can only apply to surfaces, not to theoretical centers. However, TED dimensions to centers are valid to locate the surfaces relative to the datum...

Another important difference between the ISO and ASME standards, in the context of what you need, is that in ISO in order to apply a simultaneous requirement between two or more geometric tolerances of position or profile, it’s not enough for them to reference the same datums in the same order...

Obviously, that was a false assumption and was just dismissed by the OP. Why assume someone would do such amateur work in the first place?

PtoMonty, Since there are floating components in the assembly, would it be correct to say that one press-fit pin will locate and the other one will clock similarly to the hole-then-slot mating method I described, or is there no such division of roles?

PtoMonty, An important question we forgot to ask you is: what standard do you work to? The suggestions and discussion so far were based on the implicit assumption that the drawing would follow ASME Y14.5, but if you work to ISO, there should be some modifications to the symbology to convey...

My suggestion to use the locating holes as datum references at MMB was not based on "the standard shows a picture of that case," but because, as I clearly stated in my earlier explanation, "The datum selection should reflect the function and mimic the assembly condition." That means that if the...

3DDave, You have not suggested MMC (and I didn't say you did), but you claimed this: My MMB suggestion was related to using a pattern of two holes as a locating datum reference (meant to be secondary), as suitable to the OP's description of the "actual part." My suggestion had nothing to do...