NURBS Surfaces - Curve Construction
NURBS are great for creating surfaces from curves, mathematically defined surfaces, and smooth shapes that are easy to sculpt without having to select lots and lots of vertices. This is an example of using the Revolve command to create a shape based on a curve.
First, go into the Front View and select the CV Curve Tool (Create->CV Curve). Draw a curve by clicking on points to place CV's. Press Enter to complete the curve.
Now, go back to the Perspective View, select the curve, and go to Surfaces->Revolve.
If you had history turned on, then the CV curve and the NURBS surface are still connected - if you edit the curve by moving it or manipulating CV's, it will modify the surface too. So, you can create the curve with a general idea of the shape you want, and then adjust it after you've done the Revolve command.
You can't export NURBS surfaces, so convert the surface into a polygon surface by going to Modify->Convert->NURBS to Polys. Again, with history, the polygon surface is still controlled by the NURBS surface and by the original curve - so any changes you make will automatically update the polygon surface.
(c) Ben Chang