ABSTRACT
A hazard in the use of chucks is the possibility of leaving a chuck key in position. When the machine is then switched on, the chuck key can fly in any direction and cause serious injury. When you remove a drill from the chuck, always remember to remove the chuck key. Never leave it in the chuck for even the shortest time. Better still, use a safety chuck key, Fig. 8.4, in which the central pin is spring-loaded and has to be pushed to engage. When the force is released, the pin retracts and the key falls from the chuck.
