Problems with stl-file face normals

Hi everyone,

have somebody any idea, how I can avoid such shading problems with a CAD model import in Blender. I get this ugly triangles instead of an homogenous round surface. I have tried to Merge Verticies, but the result is more ugly :wink:

Thanks a lot
Andreas

Hi gromit26b,

I am not sure but I thing the stl file might be already triangulated before importing. You can see it in the wiki image on the right: https://en.wikipedia.org/wiki/STL_(file_format) .
The only solution I thing it´s to clean by hand (merge vertices and dissolve edges). :sweat_smile:
Can you share the blend file ?

CAD data can be a bit sloppy. MoI has an option to export quad meshes, but for the most part, CAD files will be triangulated. You can try various clean up processes like tris to quads, merging verts, limited dissolve, and so on, but in many cases there will have to be some manual work done if you choose to manipulate CAD data beyond translation, rotation and scale. Most of the time for me I get fairly good results just by adding smooth shading as long as the mesh has enough resolution.

Hi aallyn and ajm,

thank you for your reply. Unfortunately I am not allowed to share this file. So it seems there is no easy trick to clean this data. If i find a solution i will report it.

Thanks and by
Andreas

If you have the CAD file as a nurbs file like STP (STEP), you could use MoI to generate improved meshing.
The MoI trial allows you to export for a limited time.

There is also a Blender STP importer https://gumroad.com/l/stepper

If you don’t have access to the CAD model, there is a quad remesher for Blender https://exoside.com/quadremesher/

Hi Everyone,

my solution is .fbx! I have import the step file in Fusion 360 and export as .fbx.
Works perfekt with a wunderfull mesh.

Thanks for your support.
Andreas

1 Like

Not sure how you did it, I still get triangulated meshes when using .fbx, but glad it worked for you.

Triangulated seems not to be the problem. I also get such a mesh, but it shades perfekt now.