1. Select the spline to lathe. The spline must be drawn in the front or right window. The revolution is made around the y-axis.
2. Click Shape in the main tool palette.
3. Click Lathe in the lower tool palette.
4. Set the Lathe Options parameters as desired.
5. Click OK to create the shape, or click Cancel to abort.

Lathe Options:

Step - The number of vertices along the u-axis The minimum number is 4. The higher this number, the rounder the final shape will appear.
Degree - The spline will revolve (counter clockwise) the number of degrees set around the y-axis.
Close - Closes the object ends.