Here are the types of machining regions you can choose from:

1.Part Regions
These are part curves that drive the location of the tool.  Defined from the Part Regions sub-tab of the Control Geometry tab for each operation.

2.Avoid Regions
These are 2D curve regions to be avoided by the cutter during machining.  They are defined from the Avoid Regions sub-tab of the Control Geometry tab for each Profile operation.

Once a Profile operation is created, new regions can be selected or existing regions can be removed from the operation as well.

To edit the list of regions used in an existing Profile operation, expand the folder corresponding to the Profile operation in the Machining Browser window.  Then double-click on the Control Geometry icon (1) or on the Profile operation folder (2). This will display the Control Geometry tab for that operation.

To Edit Control Geometry

Now you can edit the list of regions using:

•Remove All to remove all the selected regions.  

•Move Up/Move Down - these allow you to move a selected Drive Region Up or Down in the list

•Remove Active by selecting a region from the list of Selected Machining Region(s)

•Select regions using the Select buttons in the dialog.

The display of the regions in the part file can be toggled on/off using the Layer Manager.

Rhino allows you to save/export regions as curves in 3dm, Dxf, Dwg & other supported formats. Such a file can then be loaded into any part file to generate machining operations. To access the Export and the Import functions look under the File menu bar entry.