To Split a Surface Using Manual Selection
1. Click > > 
Split Surface. The Split Surface tab opens.
Split Surface. The Split Surface tab opens.2. To use manual contour selection, click 
Manual Selection.
Manual Selection.3. Click the Surface to split collector, and in the graphics window, select a solid surface or quilt to split.
4. Click the Contours collector, and in the graphics window, select contours to copy into the Split Surface feature.
5. Click the Options tab and select an option:
◦ To create several split surfaces, one for each selected contour, select For each selected contour separately.
◦ To create one split surface from all the selected contours, select For all selected contours together.
6. Click 
OK. A Split Surface feature is created that you can work on independent of the original surface.
OK. A Split Surface feature is created that you can work on independent of the original surface.