problem importing mesh from Blender

Hi all,

I’m hitting a wall trying to get a simple cylinder from Blender into Unreal Engine. I’ve spent about 8 hours on this with no luck.

Setup:

  • Blender: [ 5.0.1 ]

  • Unreal Engine: [5.5.4]

  • Export Format: Tried both FBX and GLB/GLTF

  • Mesh: Simple cylinder, basic metallic material.

The Issue:
Upon import, the cylinder shows strange dark streaks/shading artifacts on the vertical edges, looking like inverted normals.
Crucially: If I create a new basic material in Unreal and assign it to the mesh, the shading fixes itself.

Troubleshooting steps taken:

  1. Blender Side:

    • Applied all transforms (Ctrl+A → All Transforms).

    • Tried both Shade Smooth and Shade Flat.

    • a progressivily added more seams to the mesh for a better uv map

    • the current material is basic, but I initially tried one with normals, roughness, and everything else but the problem was the same."

  2. Export Settings (GLB/FBX):

    • Ensured “Normals” and “Tangents” are checked.

    • Applied scaling (Y-Up for GLB, Z-Up for FBX).

  3. Unreal Import Settings:

    • deteckt normal maps: ON

    • recompute Tangents: off

    • remove degenerates: off

Despite all this, the artifacts persist unless I replace the material in Unreal.

Does anyone have experience with this specific interaction between Blender materials and Unreal imports? Is there a setting in the Principled BSDF or export config that breaks the tangent space?

Thanks for your time!

If it’s just an issue with normals being inverted see here:

How To Inverted Normal Heights - Development / Asset Creation - Epic Developer Community Forums

Look like normals problems to me. First remember when exporting FBX you need to set in export dialog in Blender geometry>smoothing>face. Second try adding weighted normals modifier in Blender. That way when you import fbx with “import normals” option it should work. Alternatively using modeling tools mode in unreal (shift + 5 i believe) use normal tools there to calculate weighted normals inside Unreal. Modeling tools used to be plugin in unreal, no idea if it is turned on by default.