I HAVE A KEYLESS CHUCK on my cordless and corded drills, and I could never get them tight enough to prevent my drill bits from slipping. Then one day I thought about my wife’s hand-held jar lid opener, and my problem was solved. I cut two strips of insulation off a piece of old tool cord, removed the wires and slipped the insulation over the arms of the opener (to protect the plastic coated chucks).
I grip the narrow section of the chuck with the opener and the larger end with my hand. I get it so tight now that I even have to use the opener to loosen the chuck when I am finished.It’s amazing how such a simple little thing can make someone so happy!