Blender FBX mesh loses polygons when imported to UE5

Just as the title says, importing as an obj. file has the same issue also. here is what it looks like: importing issues - Album on Imgur any help would be really appreciated.

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Are you using nanite during import?

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When a polygon is missing on a 3D Mesh imported in Unreal Engine, and there is no issue with Nanite or automatic LOD generation, it might be a problem with faces normal orientation (faces are, in fact, inverted and point inwards instead of outwards). Here’s how to fix it:

  • In Blender, show the [ ] Face Orientation overlay from the Show Overlay menu in the Topbar. (Screenshot 1);
    Blue faces have a correct orientation while red faces are incorrect;
  • Switch to the Edit mode, and select each face in red;
  • From the Topbar, go to Mesh ➤ Normals ➤ Flip (shortcut Alt + N);
  • Make sure everything is blue, then export (shortcut F4).

Hope it helps!

Screenshot 1

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yup Ares nanite was the exact problem. thank you for the help!

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that wasn’t the issue this time, but I know that’s usually the common problem when importing and the detailed guide is really helpful thank you so much!

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The solution for me was to scale the mesh in blender (I did 10x), apply the transformations and export it again. It was too small.

Are you using Nanite during import too?
This shouldn’t happen (even with small meshes) if you have Nanite disabled. I often import very small meshes and I’ve never had this issue, probably Nanite generates dynamic LODs relying on the original mesh size (but this sounds really wrong to me, especially because you might want to scale meshes to a very different size from the imported one)

Nanite was disabled. I am import straight from Blender (using the official addon)