If you lost the chuck key after all these years, or just can't bear to throw away a good drill, keyless chucks are still available for most drills, and replacement is simple.
Use the chuck key to lock the jaws of the existing chuck fully open, then remove the reverse-threaded screw by turning it clockwise.
Hold the drill down firmly on a solid workbench, then insert the chuck key and hit it sharply with a mallet (turning it counterclockwise) to loosen the drill chuck from the threaded spindle. You may have to repeat this several times to loosen stubborn chucks. Unscrew the old drill chuck.
Thread the new chuck on the spindle (turning it clockwise) and hand-tighten it. Fully open the jaws of the new chuck, insert the old chuck screw (turning it counterclockwise) and tighten it. Install a bit, drill a test hole, then remove the bit and check the keyless chuck for looseness or wobble and retighten it if necessary.
Nearly every 3/8-in. drill sold today comes with a keyless chuck. Pros and do-it-yourselfers alike appreciate how fast they can change drill bits, and the convenience of not having to always hunt up the chuck key. Fortunately, the dwindling number of older reversible drills (corded or cordless) can still be converted to a keyless chuck. You can do the installation yourself in about 20 minutes.
Check the owner's manual or contact the manufacturer for the correct procedure to remove your drill's chuck; most show techniques similar to ours. Order the proper keyless chuck online or from the manufacturer, or buy a generic chuck from home centers and hardware stores. Either bring your drill along or record the number stamped into the existing drill chuck (see Photo 1) that tells the thread count for your drill chuck screw. Our stamped code, “THD 3/8-32,” reveals a 32-threads-per- inch count for our 3/8-in. drill.
Begin any chuck replacement by unplugging the tool or removing the battery. To get the old chuck off, remove the chuck screw (Photo 1). These are always reverse-threaded and quite tight, and they may require some muscle power to remove. Our chuck screw is hex-headed, so removing it required an Allen wrench. Then finish up as shown in Photos 2 and 3.
Have the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.
Avoid last-minute shopping trips by having all your materials ready ahead of time. Here's a list.