Maya 8.0 Tutorial
How to Create a Boundary Object in Maya
Boundary objects are defined by a series of CV or EP curves. In this example, we'll add four curves to the workspace.
The curves define the shape and contour of the newly created Nurbs object.
Select the CV Curve tool (Create > CV Curve Tool) and activate the Snap to Grids feature. In the side view, draw a curved line that snaps to the y-axis on the top and bottom. This is line A.
In the top view, draw a line to define the object's profile as seen from the top. The end points should snap to the x axis. This is line B.
Move line A so the bottom end point lines up with one of line B's end points.
Select line A, then duplicate it (Edit > Duplicate). Move the duplicate to the other end of line B.
Select line B and duplicate (Edit > Duplicate). Move the duplicate to the other end of line A.
Select all four lines and choose Surfaces > Boundary.
In the Boundary options, leave Common End Points to Optional. By selecting Required, all end points must line up. Output Geometry should be set to Nurbs.