Tools > 3D Features > Perfect Features removes the polygon mesh that corresponds to a 3D Feature, then reconstructs the polygons with ideal shape or leaves a void in the object where the polygons were removed.
The steps are:
In the Features group, select one 3D Feature whose shape will be used to perfect the polygon object.
In the Extension group (but only if the selected 3D Feature is a cylinder or cone), extend the end(s) of the 3D Feature so that the Feature covers all polygons that must be Defeatured in the next step.
In the Operation group, press the Defeature radio button. Set the Distance field to increase the set of polygons that will be deleted. This assures that enough polygons are deleted so that the resulting hole can be filled automatically and smoothly. Press Apply. All polygons on the 3D Feature disappear and the resulting hole on the object is automatically filled.
In the Operation group, click Union or Subtract.
Union will cause polygons to be added to the object where the 3D Feature lies.
Subtract will cause polygons to be removed from the object where the 3D Feature lies. Use this to leave a neat impression in the object where the 3D Feature used to be.
Features group - lists the one or more 3D Features on the object which can be used to perfect the polygon object.
Filter dropdown (Plane, Cone, Cylinder, and Sphere) - limits the members of the list to the 3D Features of a given type.
List of 3D Features - Click one name. The highlighted 3D Feature will be used to perfect the polygon object.
Extension group (applicable to either end of a cylinder, or the base of a cone, but not to a plane or sphere) - allows the 3D Feature to be extended. Extend a cone 3D Feature or a cylinder 3D Feature enough that it covers all the polygons that must be removed during the Defeature step.
Top Point decimal field - extends the height of the Feature along the Feature's axis.
Bottom Point decimal field - extends the height of the Feature along the Feature's axis (starting at the other end of the Feature).
Reset button (available only after Top or Base have been changed from their initial values) - restores all parameters to their initial values.
Operation group -
Unnamed set of radio buttons - specifies the action that is taken when you press Apply.
Defeature radio button and Distance decimal field - removes the polygons from the polygon mesh that touch the 3D Feature or lie within Distance of the 3D Feature, and fills the void with an orderly polygon mesh. Defeature is always the first step. Next, perform Union or Subtract.
Union radio button - constructs a new polygon mesh that matches the 3D Feature, and adds that polygon mesh to the existing object.
Subtract radio button - removes polygons from the existing object where the existing object intersects the 3D Feature.
Apply button - performs the Defeature, Union, or Subtract function.
Next button - prepares the dialog for a new operation. Press Next before picking a different 3D Feature in the Features group above.
OK button - saves modified structure to the polygon object in the Model Manager and closes the dialog.
Cancel button - terminates the dialog without saving any changes to the polygon object.