FBX Skeletal mesh - LOD import failed

Hello everyone. I have a Skeletal mesh of a NPC. I wanted to create LOD for this NPC.

So I exported my skeletal mesh by right clicking my skeletal mesh > Asset action > Export.
I used the default FBX export option.

I then opened the exported FBX into Blender 2.8. Removed the empty object named after the original UE4 Mesh (Here Enemy_A). So my Armature doesn’t have any parent anymore. Without touching anything else to my bones or my mesh (for testing purpose) ; I re-exported my skeletal mesh from blender to unreal again with theses export option :



So inside the “Enemy_A” skeletal mesh option, I imported a new LOD1 with the fresh exported skeletal mesh out of blender. The export failed, with this output log :

Notice the “Bone ‘Head_end’ not found”. I don’t have this kind of bones showing inside the SkeletonTree of the LOD0 of my enemy. And no bones with this name on my exported FBX from Unreal. So I created one inside blender and reimported my FBX into the Enemy_A LOD1. And here is the other fail log :

Now I have duplicated “Head_end” bone ? Why ? Can someone help me out making LOD for my NPC ?
Thank you very much for your time !


The original Model was made inside Maya (by another artist). You can’t just export from Unreal a mesh made inside Maya in a first place, and modify the mesh with blender to make LOD from it. Blender will add specific bones on export.

The “Head_end” bone cannot be found because it existed on the LOD version of the mesh (from blender) but not from the original model done inside maya. Blender add his own “end” bone at every bottom-child bone of an armature.

To fix it, I just replaced the base model previously made inside maya by another export from blender. So now the “Head_end” bone have a match.