To Specify the Profile Boundary
The Boundary toggle button allows you to display the boundary modifier used to control the surface defined by a positional tolerance relative to a boundary.
This button is unselected by default for every newly created GTOL symbol. It is enabled only with the Position geometric characteristic. With other geometric characteristics, this option is disabled.
When this option is used, the BOUNDARY modifier is displayed beneath the tolerance frame as shown below.
1. Click a geometric tolerance to open the Geometric Tolerance ribbon tab.
2. Click the Modifiers tab. The Boundary toggle button is available in the overflow group
3. Select the geometric tolerance and click Boundary, it is displayed beneath the tolerance frame.
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If you do not want Boundary beneath the tolerance frame, click Boundary again.