How to Repair and Replace a Drill Press Chuck

Young Woodworker using drill press
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Having an accurate drill press at your disposal is one of the key advantages that fine woodworkers have over carpenters and other craftsmen who must carry tools to the job site. Not only can the drill press fashion large, clean holes more efficiently, safely, and with far less physical effort than a drill, but the drill press also excels at other useful tasks, such as boring long spindle holes or serving as a spindle sander for sanding curved cuts created with a jigsaw or a band saw.

Additionally, a drill press can handle bits that are far larger and more precise than those typically used with portable drills. For example, it's not advisable to use a Forstner bit to cut a flat-bottomed hole using a hand-operated drill, but the drill press can handle the job effortlessly.

But In order to perform any of these tasks, the drill press's chuck—the clamping head that holds and turns the drill bits—must be in good working order. If the chuck is not gripping the bit securely or if it is stiff or out of alignment, your drill press will not operate properly, and the holes you drill will not be as precise.

How a Drill Press Chuck Works

The chuck of the drill press is typically a three-jawed clamp that tightens evenly and securely around the shank of a drill bit. Most drill press chucks are at least 1/2-inch in size (the chuck size indicates the maximum diameter of the shank it will accept), and many are 3/4 inch. The chuck is tightened by a geared wrench, called a chuck key. To install a bit, you merely insert the shank of a bit into the chuck and hand-tighten the collar until the jaws evenly and securely hold the bit, then insert the tip of the chuck key into one of the holes on the chuck above the collar, aligning the gears on the key with the gears on the chuck. Rotate the chuck key clockwise to tighten the chuck, or counter-clockwise to loosen the chuck's grip on the bit.

Servicing the chuck is often a simple matter of cleaning it while it is still in place, but once a year or so it is a good idea to remove it entirely for a deep cleaning, then reinstall it. A tool that has seen heavy use over a period of years may require a new chuck.

Tools and Supplies You Will Need

  • Air compressor or can of compressed air
  • Clean cloths
  • Drying lubricant
  • Eye protection
  • Allen wrenches
  • Mallet (if needed)
  • Open-end wrenches (if needed)
  • Replacement chuck (if needed)

Instructions

  1. Clean the Chuck

    To clean your chuck, first disconnect the power cable from the outlet for safety. Then remove any bit in the chuck, and rotate the collar so that the jaws are fully extended. Wipe the chuck clean with a dry, lint-free cloth. Next, retract the jaws completely and blow any sawdust out from within the jaw opening using compressed air. This will blow out any loose sawdust or grime from within the jaws of the chuck.

    TIP: When using an air nozzle to blow out any loose particles, wear a pair of safety glasses to protect your eyes from any flying debris.

  2. Lubricate the Chuck

    After cleaning the chuck inside and out, lubricate it by spraying a small amount of a quality drying lubricant (such as Boeshield T-9) into the open jaws of the chuck. Rotate the collar, extending and retracting the jaws a couple of times until the lubricant is worked into the mechanism, then wipe away the excess.

    If this simple cleaning and lubrication routine does not restore the chuck to good operating condition, continue by removing the chuck for a more thorough cleaning.

  3. Remove the Chuck

    On most hand-held drills, the chucks are removed by loosening a set screw inside the open jaws of the chuck, but with a drill press, the chuck has a tapered shaft that is pressure-fit within the spindle.

    To begin removal, press the tool's handle to lower the quill and chuck as far as it will go, then rotate the quill lock to hold the mechanism in the lowered position.

    Next, look for a large vertical slot within the shaft of the quill. If you find this slot, insert a chuck removal key and tap the end with a mallet to knock the chuck out of the quill spindle.

    If your chuck does not have a removal key and corresponding slot, then raise the quill until the top edge of the chuck collar is about 1/2-inch below the drill housing, and tighten the quill lock to secure the quill. Then, slide the mouth of a large open-end wrench over the quill spindle just above the chuck collar. Push up firmly on the large wrench to pry the chuck out of the quill spindle.

  4. Clean the Chuck

    With the chuck removed, wipe down the tapered shaft of the chuck with a dry, lint-free cloth. Then blow out the opening at the bottom of the quill spindle with compressed air to remove any grime or sawdust.

    If the chuck is badly worn or damaged, you will need to buy a replacement. If it appears to be in good condition after cleaning, it can be reinstalled.

  5. Install the Chuck

    To replace or re-install a chuck, raise the quill to the highest position and tighten the quill lock to secure the spindle. Rotate the drill press table out of the way so that it will not interfere with the installation of the chuck.

    Next, slide the tapered chuck shank into the quill spindle. Rotate the chuck slightly by hand until the square head at the top of the shank fits into the receptacle within the quill spindle. Retract the jaws fully, and smack the bottom of the chuck one time firmly with a mallet to seat the shank of the chuck into the quill spindle.

    Rotate the chuck collar to check the operation of the chuck, then plug in the motor and insert a drill bit into the chuck and make a couple of test bores to ensure that the reinstalled chuck is functioning properly.