After many trials for me there isn't better way to convert a #Blender's #SubD to #Nurbs #IGES. 
Using #FreeShip and #meshconv, that is the method to have perfect surfaces based on the initial topology that allows you to have total control over the final result. #b3d #blender3d
Below a tips by me on BA
https://blenderartists.org/t/from-blender-subdivision-to-n-u-r-b-s-iges-for-free/
From Blender Subdivision To N.U.R.B.S. (IGES) for free

Hi all, I have a little trick that I discovered just today and wanted to share it with you. I found an easy way to convert the subdivision surfaces, in to nurbs surfaces. To do this you need two free programs ’ FreeShip_Plus ’ and another to convert VRML format ’ 1 ’ First you need to export your files from Blender, eliminating the subdivision modifier and export to obj with the Z axis at the top, after using the program “meshconv” to convert from obj to wrl. Open ’ FreeShip ’ and import the...

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