I have an intern who’s having a really hard time weighting vertices to a character’s mesh in Blender. I’ve tried moving bones in pose mode and the mesh is deforming horribly, and I don’t know why. For example, I move the right arm and the left middle finger moves as well, though these vertices aren’t attached to the right arm. The arms just aren’t deforming correctly either, the mesh seems perfectly riggable so I don’t know what we’re doing wrong. Here’s the link for the file if anyone can have a look for themselves and put us out of our misery:
So select this group, and paint with a weight of zero over the right thumb.
Or, to be a bit more thorough about it, you should select the verts and remove them from the wrong bone vertex groups in the vertex groups panel.
The problem with weight painting with zero is that you don’t really wind up with zero weights usually, but with very low weights, which can add up if they are spread around on a bunch of different bones.
You can find out which verts are in the wrong vertex group by selecting a vertex group and pressing “select”. This will select all the verts in each vertex group.
The problem you’re having is probably caused by overshooting on your original weight painting, and getting small bits of weight paint on the wrong places. To do more careful weight painting in the future, try pressing the F key in weight paint mode to get you into face select mode so you can select the faces you want to paint and hide faces you don’t want to paint.
Also, tell the intern to SLOW DOWN and be more careful. S/he probably doesnt understand how fragile and sensitive little things like a litle overpaint can affect things. And (hopefully) wants to impress you with how MUCH they can churn out. Emphasis quality over quantity.