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In this case the Facet Body to Nurbs NURBS tool can executed once again with a smaller NURBS Face Size or the geometry can be repaired manually with the Geometry Cleanup and Filler Tools.
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With the Filler Tool the missing NURBS patches can be restored. Therefore, the automtic filler Tool can be used. For more control the Flash can be deactivated and the edges can be chosen manually. The preview helps to decide which edges belong together to create a reasonable NURBS patch. Sometimes it is ueseful to delete adjacent patches with the Split Surface tool and to recreate them then with the filler tool.
Step 3: Geometry Cleanup
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