Control rig loses bone weight paints

I’m trying to use control rig and running into a problem with weight paints. For some reason, my character loses all weight paints on the bones and instead attributes all weight paints to the root in control rig. The mesh / skeleton has proper weight paints, I can move any bone normally in the skeletal asset and it retargeted animations as well. But when I create a control rig for the mesh it loses its weight paint information and I’m not sure why. Is there a setting somewhere that I have turned on/off or is anyone familiar with this problem?

Some info:

  • I’m working in a fresh project in UE5, though I opened my UE4 and replicated the issue with the mesh.
  • I made a control rig for the unreal mannequin, which worked properly (maintained its weights)
  • The root in control rig acts as if it has 100% weight on everything even when moving it by itself (not propagating the motion to its children). However it does not display any weight paints in control rig (it shouldn’t have any), but acts as if it does.
  • Skeletal mesh behaves normally outside of control rig as far as I can tell

Some pictures:

Moving the root with propagate to children turned off, the mesh is moving with only the root

Weight paint comparison of the head with the control rig (left) vs. skeletal mesh (right)

The answer is both frustrating and simple! Control rig simply does not like “-” in the bone names, remove those and the rig will work fine (def-head => defhead).

I don’t know how or why it seemed to transfer weights to the root when the bones had dashes in their names. Also weight paints don’t appear to show in control rig even with proper bone naming, I suspect that is just a bug.

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