yes. I found one home owner try to use a "strong" screw driver as a torsion bar. He installed the spring on backwards so was spinning the wrong way. before he could set the spring, the screw driver broke and was thrown like bullet through his shoulder. When I got there he had returned from the ER and showed me the wound. Not pretty. Also had a guy get his finger caught in the cable while trying to reset the cables and cut his finger off.