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Position with different datums for spheres 1

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200918

Mechanical
Aug 26, 2024
2
Does the drawing attached make any sense?

The critical features of this part are that the two spheres are located accurately with respect to the datums A,B,C, but what is even more critical is that if you created an axis between the two spheres, that axis is perpendicular to A.
 
 https://files.engineering.com/getfile.aspx?folder=8f04a26a-e005-46c6-9033-617683b8f830&file=Screenshot_2024-08-26_120022.png
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That's not a composite position.
It is a multisingle segments positions callout.
 
The main problem is that the partial spherical surfaces are too partial to be treated as features of size, for the positional tolerances.
 
200918,

Did you model this in 3D[ ]CAD? Your spherical radii are equal. I don't think your geometry works.

Other than that, your drawing makes sense to me, and I can interpret everything. Your tolerances are super precise. Can you inspect this? Can anybody fabricate it?

--
JHG
 
Hi, 200918:

Your drawing view is fake. Those two spherical radii are different visually. Yet, they have the same dimension SR99.00.

Best regards,

Alex
 
I basically agree with the comments of the others. However, to achieve your stated objective, I suggest establishing a datum circle on each SR at a gauge distance from datum A, then applying a position tolerance on the center of the smaller datum circle back to datum A and the larger datum circle. I think that this would provide the perpendicularity control that you seek while overcoming the gaugeability problems noted by others. It may even allow you to relax some of the other tolerance controls.
 
Thanks for the feedback. The two radii were intentionally changed for the purposes for public posting, they are different in reality.



 
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