To Merge the Knots of Two Surfaces
Make sure that the parent surface has knots defined before you begin.
1. Click 
Style > 
Surface Edit. The Surface Edit tab opens.
Style > Surface Edit. The Surface Edit tab opens.2. Click the Options tab, and select the Advanced Options check box. The knot functionality is turned on.
3. Select the child surface to align. Make sure that the control mesh is displayed.
4. Right-click the mesh boundary between the child and the parent surfaces and choose an Align command from the shortcut menu.
 | The Align commands are available only when the Preserve None mesh boundary constraint is selected. |
5. Click the Align tab, click the Neighbor surface collector, and select the edge of the parent surface to which you want to align the child surface. The surface continuity is selected in the Constraint box according to the type of alignment you selected.
6. To limit the alignment operation to a portion of the curve, perform one of the following actions:
◦ Drag the handles in the graphics window.
| | Press and hold SHIFT while dragging to snap the handles to a reference. |
◦ Click Details. In the Chain dialog box that opens, click the Options tab. Type a value for the start or end of the curve, and click OK.
7. To specify the child surface, click the Side surface collector and select a surface.
8. To change the continuity level, select a new constraint from the Constraint box.
9. Under Knots Matching, select the Merge Neighbor Knots check box. The knots are aligned.
| | You can click >  Knots to open the Knots analysis tool and display parent surface knots. |
10. Click 
OK.
OK.