Hi Bravlin,

re:
> I examine Karsten approach to this shape reconstruction.
> At first look everything looks great. But i found surface artifacts.

The first one looks like only a display artifact, not in the actual surface. If you export to a mesh format and make the mesh higher density it should go away.

It's a type of artifact that happens when the display mesh ends up with some sparse longer triangles across an area where the normals are changing.

The regular viewport display is more tuned to generate display meshes quickly so that you don't have wait extra time on every modeling operation. To get a better view of surface quality you can set up a keyboard shortcut that does a SaveAs to a mesh format like: SaveAs c:\bugs\test.obj then crank up the density and cancel when you're done without actually writing the file.

The other one though running through the centerline looks like a tangent discontinuity. That could be improved by trimming away some space and putting in a G2 blend surface like in the attached version.

- Michael