Removing doubles causing face distortion

Hi guys, I’m making this hair (anime like) and I joined two meshes, internal and external:

With mirror, the hair looks oks, but when I use “Remove Doubles” on all vertices, it appears that the faces mess up! Just like that:

Can anyone help me?

Thanks a lot

Remove inside faces, doubles and recalculate normals outside (ctrl+n).

But at the end I’ll not have the inside faces and I really want them =(

I’ve read all your post and undesrtood some basics, but I can’t get it to work. I searched for interior faces and non-manifold but blender returned none of them. Can you help me looking at the blend file itself?

Thanks in advance


hair.blend (829 KB)

Mesh being non-manifold is not necessarily a bad thing, just have to be aware of it because it affects normals calculation. That’s not the problem here. Only a shading problem but I’ll point out couple of other potential problems first.

  • There’s the interior face (painted red and highlighted in orange) that needs to be removed. It becomes an interior face (and a topology problem) after the mirror modifier adds the mirrored mesh and merges vertices along the mirror plane.
  • Object scale is not 1 (highlighted with red arrow). This is quite often the problem when there’s a misbehaving modifier or some tool doesn’t work right. It means that you have scaled your object in object mode and that changes the representation of the model, while in edit mode edges still are the same length. Ctrl+A -> scale in object mode to apply the scale for the mesh, or alt+s if you want to clear the object scaling.

  • Front hair has thickness and edges around it are very sharp. Smooth shading tries to set the shading so that the front edge appears round and fails miserably. To fix that, those edges have been selected and marked as sharp (ctrl+e -> mark as sharp). Then a edge split modifier is added and set to only split edges that are sharp.

Not sure if this was what you were looking for but yeah… can’t think of anything else. It’s about the materials/textures/lighting after that.

Thanks JA12 !! Now I got it! =D

Ur awesome!