See the rig and select bones in mesh weight painting mode.
- Select the rig
- Put the rig in pose mode.
- Shift-select the mesh. Both the rig and mesh are selected, but the mesh is active.
- Switch to Weight Paint Mode
- Hold the Control Key (Mac) and select the bones. It will show the weight painting associated with the selected bone.
Add a bone to a vertex group if you created the bone after parenting the rig to the mesh and it does not show up in the vertex group.
- Select the rig
- Put the rig in pose mode
- Select the bone that is missing.
- Shift select the mesh. Both mesh and rig are selected, but the mesh is active.
- Make sure you see the missing bone selected (highlighted in blue).
- Go to Weight Painting mode. If the mesh turns pink, that means the selected bone has no vertex group (as suspected).
- Set the Weight and Strength to 1.0 of the brush.
- Paint the desired area on the mesh and the bone will be automatically added as a Vertex Group.
Use Edit Mode to Weight Paint vertex groups.
See vertex groups in Edit mode
Sometimes Weight Painting and assigning vertices to vertex groups is easier to do in Edit mode the Weight Paint mode.
- Select the rig
- Put the rig in pose mode
- Select the bone that is missing.
- Shift select the mesh. Both mesh and rig are selected, but the mesh is active.
- Go to Edit mode.
- Choose the Object Data Properties palette (green triangle) to see the Vertex Groups.
See the vertices assigned to the vertex group in Edit mode
- Deselect all vertices by clicking outside the object.
- Select the vertex group.
- Choose Select from the Vertex Group menu to see the vertices/edges/faces that are assigned to that vertex group.
Assign vertices to a Vertex Group
- Select the desired vertices in Edit mode with either vertex, edge, or face select mode.
- Choose the desired vertex group.
- Press the Assign button. Note: this will delete all prior vertices associated with the group and re-assign them to the currently selected vertices.
Remove vertices from a Vertex Group
- Select the vertices to remove.
- Choose the desired vertex group.
- Select the Remove button.
Note: this can be tricky as you will remove the vertices that are selected, but you can’t see the vertices that are associated with the vertex group. Choose the Select button to see the assigned vertices again.
Fix a bone that has totally messed up Weight Painting.
- In Edit mode, select all the vertices by pressing the A key.
- Choose the desired vertex group to reset.
- Select the Remove button. This will remove all mesh vertex association with the bone and clear all weight painting.
- Select the mesh vertices that you want associated with the bone/vertex group.
- Press the Assign button to assign the new vertices to the vertex group.