Boundaries > Extend Boundary projects a selected natural boundary in the direction suggested by surrounding surface. Examples: The boundary at the lip of a volcano can be extended such that the volcano becomes a more complete cone; the boundary at the lip of a tapered drinking glass can be extended such that the glass becomes taller with a uniform taper; the boundary of a hole in a flat surface can be extended such that the hole becomes smaller.
Typically, use Boundaries > Relax on a boundary before extending it.
Set the extension parameters.
Click a boundary of interest in the Viewing Area.
If the most recent extension action is acceptable, press Next.
If necessary, go to Step 1.
Click OK to save modifications to the object in the Model Manager (or Cancel to revert to the initial condition).
Extension group -
Length decimal field - specifies the distance of the extension.
Sharp Edges checkbox and Crease Angle decimal field (0 to 180) -
Smooth Boundary Curve checkbox -
Relax integer field (0 top 100) - is a degree of relaxation (removal of sharp turns) to apply to the boundary before any extension.
Curvature Continuity Extension checkbox - specifies that extension follows the curvature of the surrounding surface, rather than a line that is tangent to the surface.
Reset button - restores defaults in the dialog and un-selects all boundaries in the Viewing Area. To resume work, start by clicking a boundary in the Viewing Area.
OK button - saves all extensions to the object in the Model Manager and closes the dialog.
Cancel button - terminates the dialog without saving any extensions to the object in the Model Manager.
Next button - prepares the dialog for a subsequent extension. If you don't press Next between extensions, the previous extension will be lost.