To Approximate Offset Surfaces
Use the following procedure to create approximate offsets for surface patches that cannot be offset precisely.
1. Select a surface, and click Model > Offset. The Offset tab opens.
2. Select Standard to create a standard offset.
3. Click the Options tab.
4. Select Normal to Surface from the fit type list.
5. Click the Special Handling collector, then in the graphics window select individual surfaces to approximate; or click Auto to add all surface patches that cannot be offset precisely to the Special Handling collector.
6. Select Approximate from the list next to each surface to approximate, or click Approximate All to set all surfaces in the Special Handling collector to Approximate.
7. To attach approximate offset surfaces to adjacent standard offset surfaces when the approximate surfaces cannot be merged with the standard offset surfaces, select the Attach approximate offset surfaces check box.
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To approximate adjacent surfaces, the adjoining edges must be tangent to each other.
8. On the Offset tab, type an offset value in the Offset box.
9. To reverse the direction of the offset, click , or right-click and choose Flip Side from the shortcut menu.
10. Adjust the offset distance and direction by dragging the handle or by double-clicking the dimension in the graphics window and then entering a new dimension in the box.
11. To create the offset surface with side quilts, click the Create side surface check box on the Options tab.
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When you choose to approximate a surface, the Create side surface check box is unavailable.
12. Click OK.