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Primary datum as a sphere?

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theedudenator

Mechanical
Jun 15, 2006
27
Imagine the a tie rod end.
The sphere component has a shaft protrusion.
For functionality in the assembly, the sphere is the primary datum.

If I called out the diameter of the sphere as the datum would be it be a center point? Or a set of perpendicular planes?
 
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I have a sketch showing what I want.
Not sure how I post it.

 
Perhaps you could use the protrusion as a datum feature, A, and the dia of the sphere as B. Then you could make ref to axis A-B.



 
I could do that... but in the application the sphere is clamped and completely constrained. Except for rotation.
 
Specifying a sphere as a Datum Feature of Size gives you a point in the center (vs the axis of a cylindrical feature of size), which has three mutually perpendicular planes centered at that point (there are two mutually perpendicular planes associated with the axis of a cylindrical feature of size). The planes are the datum planes from which measurements are taken.



Jim Sykes, P.Eng, GDTP-S
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But this center point of the sphere defines how the remaining geometry is created.
I understand it is not a plane, but it is the most important location for assembly reasons.
 
How Can I Show An Image In A Post
faq559-1100

Chris
SolidWorks 06 5.1/PDMWorks 06
AutoCAD 06
ctopher's home (updated 10-27-06)
 
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