Turn off the drill press and unplug the machine.
Turn the "Depth Scale" wheel, which is the three-pronged wheel above the chuck, to 3 inches.
Rotate the chuck by hand so that the two keyholes are visible in the vertical opening in the spindle. The spindle is the piece located just above the chuck.
Insert the key wedge into the keyholes. The key wedge is a proprietary tool included with the the Craftsman drill press. The key wedge is a piece of metal with two prongs on the end that fit snugly into the two holes.
Place one hand below the chuck, then tap the key wedge lightly with a mallet until the chuck falls out of the spindle.