I keep running into this problem. I have tried to rebuild this mesh three times now... I'm building a flat mesh on the X + Y Axis only using extrusion Ctrl + E, Shift + Zetc. When I finish I keep getting doubled faces, indicated by the different shading on the affected faces. (I'll attach screengrabs). What is the best way to fix this?

I have tried Clean Up > Merge by Distance, but it removes loads of faces entirely, not just the doubles, and then bizarrely I can't add the face back by selecting the vertices and pressing F. If I select all the affected vertices and delete faces it deletes both faces.

Help in this matter would be greatly appreciated, thank you.

enter image description here

  • $\begingroup$ After using the Merge by Distance function it removed 90 vertices. And left odd shading on the affected faces as in the screenshot above. In addition it left strange artefacts when I added Solidify modifiers and Subdivision Surface. In the end I just went through manually and deleted the extra vertices as it was quite a simple mesh. I did this by double clicking each doubled vertex, a single click chose the one underneath and the second click chose the top - I don't know which was correct to delete or if it mattered. But it seems to be fine now. $\endgroup$
    – Aubrey
    Apr 11, 2020 at 13:55
  • $\begingroup$ I would still like an answer to this question if anyone with experience has run into this before. I'm not sure at what point in the process of extruding and building the 2D flat mesh it starts adding extra vertices and faces but when it does how do I remove them in a way that doesn't leave artefacts as it did after using Merge by Distance. $\endgroup$
    – Aubrey
    Apr 11, 2020 at 14:01

1 Answer 1


Revisiting this for continuity. And answering my own question. I continued to have this issue, with doubled faces and inconsistent 'shading' on the faces on further mesh builds, using Extraction E to build a flat (2D) mesh.

There were two problems: Duplicate vertices and Normals direction of the faces.

Because it was a simple mesh I was able to remove the doubled vertices manually. But it can also be solved using the command from the 'Mesh' Drop down: Clean Up > Merge by Distance. Although this doesn't always seem to behave perfectly and may still require some manual work.

This didn't always result in accurately recalculating the normals either. One can recalculate normals from the same Menu 'Mesh' > Normals > Flip, Recalculate, Rotate etc. But to do individual faces they need to be manually selected I believe.

To choose individual faces use Face Select mode 3 and Recalculate or Flip only selected faces.

In all of this I wasn't able to figure out why Blender sometimes (seemingly randomly) flips the normals or duplicates vertices, but with a little diligence they can be adjusted as one is building the mesh.

I hope that helps someone who is encountering a similar problem in their early days getting their head round Blender.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .