Click Tolerancing Advisor
The Semantic Tolerancing Advisor dialog box appears.
Multi-select the three spheres as shown:
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The Semantic Tolerancing Advisor dialog box is
updated according to the selected surfaces.
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As you can notice, there is no Semantic Datum
icon in the dialog box because it is not possible to create
a datum on non-canonical surfaces, compare with
Creating Semantic Datum and Datum Targets. To do this, you have to redefined the geometric
surface to consider the non-canonical surfaces as an unique
surface.
Select One Surface in the Geometry feature
type combo list in the Semantic Tolerancing Advisor
dialog box.
The Semantic Datum icon is now available.
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Click Semantic Datum icon (One surface):
The Datum Definition dialog box appears.
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To define the unique surface representing the non-canonical
surfaces, you have to select a plane which represents the orientation
of this surface.
Select the Plane direction field in the
Datum Definition dialog box, and select the surface as shown
on the Support component.
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The Plane direction field contains the representing
surface:
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Click OK in the Datum Definition
dialog box.
The datum is created.
Click Close in the Semantic Tolerancing
Advisor dialog box.
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