Do I Need a Keyed or Keyess Chuck?
The chuck is the attachment on the tip of the drill where the drill bit is inserted. It has jaws that grip the bit as it is tightened. Drills come in 1/4″, 3/8″, and 1/2″ sizes. This measurement is the chuck size and indicates the shaft diameter of the bits and accessories that will fit the drill. For most homeowners, a 3/8″ size should be sufficient. Chucks can be keyed (the jaws are tightened or loosened with a key) or keyless (the chuck can be tightened or loosened by hand). Keyless chucks offer two major benefits. If you have ever misplaced or lost a chuck key, you already know one of them. A keyless chuck will also allow bits to be changed more quickly. A real plus when you need to change from a drill bit to a screwdriver bit repeatedly or if you happen to be wearing gloves on the job. You can change the chuck in some keyless models with only one hand because the shaft locks when the trigger is off. In most models, however, you have to use both hands to turn the chuck in opposite
