To Split an Area
1. Click > 
Split Area. The Split Area tab opens.
Split Area. The Split Area tab opens.2. The Placement tab is open by default.
3. Perform one of the following operations:
◦ When a sketch already exists, click Unlink to break the association with the sketch. An internal sketch is created using a copy of the sketch. Create a sketch and click 
OK.
OK.◦ When a sketch does not exist, click Define and set references. Create a sketch and click OK.
OK.4. Click 
to create the split area normal to the driving surface or click 
to create the split area normal to the offset surface.
to create the split area normal to the driving surface or click to create the split area normal to the offset surface.5. Accept the default projection direction or click 
Projection Direction to project the sketch to the other side or both sides of the reference plane.
Projection Direction to project the sketch to the other side or both sides of the reference plane.6. Accept the default area selected for the sketch or click Sketch Direction to toggle the location of the new surface ID to the area inside or to the area outside of the sketch.
Sketch Direction to toggle the location of the new surface ID to the area inside or to the area outside of the sketch.7. 
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