To Delete a Trimmed Surface Boundary
1. Select one or more one-sided edges of the trimmed surface boundary in the graphics window or on the GTS Tree.
2. Right-click in the graphics window and click Delete. You can also press the DELETE key. The selected one-sided edges of the trimmed surface boundary are deleted.
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If you delete the outer trimmed boundary of a surface, all internal trimmed boundaries are also deleted. However, you may delete internal boundaries independent of the outer boundary and other internal boundaries.
You cannot delete a part of an outer trimmed boundary. The outer trimmed boundary of a surface may be made up of two or more edges. You may select only one edge of this trimmed boundary to delete but all the edges of the boundary are deleted.
When you delete an outer trimmed boundary for a free form or spline surface, the surface acquires a new rectangular outer contour corresponding to the natural domain of the surface. For an analytical surface, the surface acquires a new envelope when its trimmed boundary is deleted.
You cannot delete two-sided edges.