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Please see an attached picture and

Please see an attached picture and

RE: Please see an attached picture and

cmmguy75,

Thank you for deleting your post in Mechanical Engineering.

As I noted before, your old drawing is missing tolerances, therefore, the new drawing is better. Using a line through two holes as a datum for an angle should be legal as per ASME Y14.5, if this were my drawing, probably I would rotate the view 45° and use the slot as my tertiary datum. The holes would be located by positional tolerances.

--
JHG

RE: Please see an attached picture and

I'm trying to come up with a better response than "both suck".

Neither does a complete job of constraining or defining. Hard to tell what you're after.

RE: Please see an attached picture and

New drawing:
Why not delete 45° from the edge of the pocket and keep 45° basic from the centerline of the .501 pocket?
Why not position for the pocket to control its location? (size / width can be controlled by the size dimension as shown).
Profile with no datum will control only the form and not the location.
Datum reference frame will be probabbly: A primary (the flat face surface), B secondary hole or pin and C tertiary (hole or pin).
No need for .2505 basic if position is used (no need for half dimensions)
Profile can be used (maybe even all around profile) then the pocket geometry should be basic including its bottom angle (currently not defined) and .501 should be basic.
Profile should have some datums (maybe A, B and C) to define its location. No need for " after .0005.
If you tell us more how this part works/ functions, we (probably) can tell you more on how to define it and how your drawing should look like.


RE: Please see an attached picture and

Quote (CMMGUY75)

Is the new attached file a better callout?
No. It is NOT.
Never attach datum feature symbol to the centerline. Profile callout should be shown with a leaderline or an extension line of the surface "Where an equally disposed bilateral
tolerance is intended, it is necessary to show the feature control frame with a leader directed to the surface or an extension line of the surface, but not to the basic dimension."

If you just want to use profile make .501 basic, as I stated before. I would not say the profile is the right tool for this job.
Position would do the job.

If you don't want to say how this part works nobody can give you a good solution. If you don't know, maybe the designer knows. Someone has to know how this part works.

RE: Please see an attached picture and

greenimi,

The OP's drafting tools are crap. It looks like he is the inspector, not the drafter.

My interpretation is that the features for datums B and C are holes. Specifying an angle from a line defined by two holes sucks, especially if the diameters are not accurate. This is why I suggested using the accurate slot as a datum. Still, the scheme can be interpreted by ASME Y14.5.

The new dimensioning scheme is not complete, as it does not control the angle of the slot. The profile tolerance looks like an attempt to control symmetry. I am not sure it matters here, but my general assumption is that tolerances on FOS datum features need to be sloppier than the datum feature.

--
JHG

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