WHILE ATTEMPTING TO REINSTALL A CABLE ON THE PULLEY FOR THE MAN CAGE GATE, A 4 X 4 X 6 PIECE OF WOOD WHICH WAS BEING USED TO PROP THE GATE UP FELL DOWN THE SHAFT AND DAMAGED THE BELL SIGNAL CABLE. THE SHAFT WAS INSPECTED, THE CABLE WAS REMOVED AND THE HOIST PUT BACK IN SERVICE.