Create a Datum Plane
- 
                From the HyperGraph 3D toolbar, click the Datum
                    Planes icon,  . .
- Click Add under the Datum list.
- Select the plane type: Reference plane, Cross section, or Clipping plane.
- 
                Under Method:, set the orientation method: 
                - Vertical along the Z axis  
- Horizontal along the X axis  
- Horizontal along the Y axis  
- Three points  
 
- Vertical along the Z axis 
- Click two points on the curve to define the Orientation points.
Or
- 
                If you selected Three points, click three points on the
                    curve to define the Orientation points.
                The plane passes between these points along the Method axis.
