a quick stop device for abruptly interrupting the cutting of a workpiece by a cutter is disclosed . the quick stop device employs an outer housing connected to an inner workpiece holder by at least one shear pin . the outer housing includes an appropriate shank designed to be received in the spindle of a machine , such as a machine tool . a cutter , such as a drill bit , is mounted in a stationary position and the workpiece , mounted to the workpiece holder , is rotated during engagement with the cutter . a trigger system includes at least one spring loaded punch disposed for movement into engagement with the workpiece holder to abruptly stop rotation of the workpiece holder . this action shears the shear pin and permits continued rotation of the spindle and outer housing without substantially disturbing the chip root formed during cutting .