Boundaries > Extrude Boundary projects a selected natural boundary in a positive or negative direction and inserts triangles to fill the space between the old and new positions. The direction is usually perpendicular to a plane suggested by the boundary. If the boundary does not suggest a plane, results are less predictable.
One use of this function involves the scanning of holes on physical parts and the cleanup of those holes on a polygon object. The interior wall of a hole is difficult to scan with most equipment. This function allows the interior wall to be extrapolated from a boundary at the top of the hole on the polygon object.
Depth radio button - controls the characteristics of extrusion.
Value decimal field - controls the depth of the extrusion.
Close Bottom checkbox - specifies whether to create a flat, closed surface at the end of the extrusion.
Connect radio button (applicable when two or more natural boundaries exist on the object) - specifies that the next two boundaries that you click in the Viewing Area shall be connected.
Next radio button - cuts a hole (rather than creating new mesh) through the first layer of mesh that is encountered on the path of the extrusion.
Through radio button - cuts a hole (rather than creating new mesh) all the way through the object on the path of the extrusion.
Axis Datum group - The default direction of extrusion is perpendicular to a plane suggested by the boundary. This dropdown allows the selection of an existing axis datum (as created by Tools > Datums > Create Datum) whose direction overrides the default direction.
Axis Datum dropdown (a list of existing axis datums).
Set button - establishes the datum that is currently selected in the dropdown as the determinator of the direction of extrusion.
Intersect checkbox - causes an extrusion to cut through any interior geometry that may lie in its path.
Clear button - removes the selection of all boundaries in the Viewing Area and resets the dialog.
Execute button - converts a preview to a result. The polygon mesh is extended or deleted per the settings in this dialog.
OK button - saves the modified object to the Model Manager and closes the dialog.
Cancel button - restores the object to its original condition and terminates the dialog.
Reset button - restores the object to its original condition and leaves the dialog open for further extrusion.
To extrude a single boundary and extend the polygon mesh:
Click the Depth radio button.
Select one boundary that will be extruded.
Adjust the distance of extrusion by setting the Value, and
Click Close Bottom if the end of the extruded section must be capped.
To extend the polygon mesh between two existing boundaries:
Click the Connect radio button.
Select one boundary in the Viewing Area. A preview of the extrusion appears with white lines.
Accept the preview by pressing Execute (or press Clear to reset the dialog). The white lines change to a new polygon mesh.
To remove the first layer of polygon mesh that is encountered on the extrusion path:
Click the Next radio button.
Select one boundary in the Viewing Area.
Accept the preview by pressing Execute (or press Clear to reset the dialog). The first layer of polygons on the extrusion path are deleted.
To remove all polygons that lie in the extrusion path:
Click the Through radio button.
Select one boundary in the Viewing Area. A preview of the extrusion appears with white lines.
Accept the preview by pressing Execute (or press Clear to reset the dialog). All polygons on the extrusion path are deleted.