When I added automatic weight paint on the thumb bones it looked ok but when I bend the joints the mesh seems like its being pulled apart by two opposing forces. This never happened before when I deleted the original thumb bones or maybe it did but I didn't notice much either way why is it acting like this?enter image description here

  • 1
    $\begingroup$ hello maybe share your file so that we can give a try? $\endgroup$
    – moonboots
    Commented Nov 10, 2021 at 6:53
  • $\begingroup$ (How to add a blend file) $\endgroup$ Commented Nov 10, 2021 at 14:12
  • $\begingroup$ Hold on I'll give it to you just need a little time. Also what's the max limit for data when sharing a file on Blend-Exchange? $\endgroup$
    – Stephen
    Commented Nov 11, 2021 at 0:32
  • $\begingroup$ Sorry for the wait did you get it? $\endgroup$
    – Stephen
    Commented Nov 12, 2021 at 3:27

1 Answer 1


Automatic weight paint isn't perfect, and what has probably happened is that the thumb mesh has vertices in more than one vertex group, that is assigned to more than one bone. When you pull the thumb, the influence of the other vertex group (and thus bone) interacts, so the mesh distorts.

If you go into edit model on the mesh and select one of the vertices that are being pulled the wrong way, the side panel will show you all of the vertex groups it is in. You can either remove it from the other vertex groups, or go into weight paint mode and change the paint for the vertex.

It's usually better to use weight painting at that point, because there are bound to be other nearby vertices that have the same problem.


You must log in to answer this question.

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