What I'm trying to do is create a robotic hand. I created the mesh and added the bones for the fingers (following CG Cookies' tutorial on rigging fingers), but didn't add a bone for the "arm" part of the mesh.
I've tried adding the bone (the arm bone is named Bone.020), created a vertex group with the same name, then weight painted the part it should move, but that didn't work. I have tried parenting the finger bones to the arm bone, but that didn't work. I don't know what else to do. Any help is greatly appreciated.
Texture Used In File (not necessary)
View of the Bone Constraints panel
Showing the fingers are working properly
The problem - Rotating the arm doesn't pivot where the "elbow" would be
Example of weight paint that works with thumb