To Align Boundaries while Editing Surfaces
1. Click 
Style > 
Surface Edit. The Surface Edit tab opens.
Style > Surface Edit. The Surface Edit tab opens.2. Select a surface to edit.
3. Adjust the mesh density using the Max rows and Max columns boxes.
4. Right-click the boundary of the mesh to be aligned with a neighbor and choose Preserve None, or right-click the surface and choose Clear All Boundaries from the shortcut menu.
5. Right-click the boundary of the mesh and choose an align command.
6. Click the Align tab.
7. Click the Neighbor collector and select a reference by performing one of these operations:
◦ Select the edge of the neighboring surface.
◦ Click Details. The Chain dialog box opens, where you can select one or more edges to define a chain.
8. To trim the aligned edge, drag the handles, or double-click an endpoint value in the graphics window and type a new value.
9. Click the Side surface collector to add a reference in the following cases:
◦ A two-sided edge as the neighbor for a tangent continuous or curvature continuous alignment—Select the parent surface.
◦ An Align Normal Position operation—Select a reference plane to define the normal direction.
◦ An Align Normal operation—Select as a reference a plane or a surface that belongs to the selected edge or Curve on Surface to define the neighbor reference.
10. Right-click the graphics window and choose Deactivate Collector from the shortcut menu.
11. To further define the alignment, perform any of the following operations:
◦ To reverse the direction of the tangent or curvature, right-click the aligned boundary and choose Flip from the shortcut menu. This command is not available for an Align Position operation.
◦ To switch the start and end points of the align boundary, right-click the aligned boundary and choose Swap Ends from the shortcut menu. This command is not available for an Align Normal operation.
12. To finish the alignment operation, perform one of the following operations:
◦ Middle-click the graphics window.
◦ Right-click and choose Complete Align.
13. Click 
OK.
OK.