Smooth splines as edges for object

Hello everyone,

a while ago I created a 3D model of a ship. I used Blender for the editing. Obviously the Blender model only contents vertices, edges and faces, that you can make look smooth in Blender although they not really are.

Now I would like to create some technical drawings from the shape. Therefor I’d like to transfer it to AutoCAD (other software from Autodesk would be possible as well) without having to entirely rebuild the ship within the new software. Therefor some of the edges/surfaces need to be smoothly curved. Every edge should still cross all its vertices, but many of them as a “spline” instead of a straight line. I need a really smooth mesh.

Does anyone of you have an idea, how to archieve this? I did a lot of research already for this and tried to replace edges (and the entire mesh) with bezier curves, but none of this brought me even close to what I need. My bezier curves are still straight lines from vertex to vertex and nothing changes when I edit the weight/radius/tilt. I could even create some code in python for this, if I only knew what to do.

Thanks a lot in advance for every hint that you can give me!


I would say that you are searching for smooth shading applied to faces before exporting. Note though that edges can’t be smoothed or behave as splines by definition; they are defined by vertices holding them. Geometry of the mesh object based on edges then is as smooth as many subdivisions of edges and faces there are. But every edge still remains strictly straight.
There are other types of objects which work in a different way, e.g. Nurbs surfaces. They indeed have 4 vertices for one piece of surface and handles like curves have which define smothness. However Blender doesn’t appear to have good tools to operate on that geometry (though it can create and edit it) and it’s not possible to export it.

It would be probably helpful if you show a screenshot of what are you after and what you’d like to achieve.

I think better option would be software like CATIA(Imagine an Shape) or Creo, they can import obj files made with blender and convert them to NURBS surfaces, also you can use T-Splines with Rhino. Autocad isn’t the best choise for ship design.