About Neighbor Knots
You can merge a surface's knots with the knots of a neighboring, aligned surface to increase continuity and to exactly match the boundaries of two surfaces. You can drag knots after merging, and then realign them. You can also replace the knots of one surface with those of a neighboring surface.
You can match and merge knots between two surfaces with untrimmed edges, or between the knots of one surface and COS curves that lie on isolines.
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These operations are not available if one of the neighbor surfaces does not have knots—for example, a planar surface.
In a Merge Neighbor Knots operation, you designate a parent surface and a child surface. You can use the Knots analysis tool to display the knots of the parent surface, and then open the Surface Edit tool to modify the child surface knots.