Game Art: Robot // Arm Problem

After binding my character I encountered a problem that took me a  while to solve. Both the arms where not working the way I wanted them to, every time I rotated the arms, the drills where not staying attached to the the arms. Below is an illustration of the problem. 

It took me a while to figure out how to solve this, I first started by going back to a previous scene I had saved to freeze the transformation, re-constrained the skeleton and rigged it again. I then weight painted it again, I flooded the right joints with 0% influence to make it rigid. The arm then worked properly, there was no way I could have gone on without fixing this issue.