Black & Decker manufactures a number of popular electric drill models. Many of these drills are equipped with a keyed chuck from the factory, which can easily be changed out in favour of a keyless chuck. The original chuck on a Black & Decker drill can be removed from the electric drill's driveshaft after removing a screw from inside the jaws of the chuck.
Disconnect the electric drill from the power outlet.
Open the jaws of the chuck to the widest point by turning the chuck counterclockwise.
Insert an Allen wrench into the screw located between the jaws of the chuck, and remove the screw by turning the wrench clockwise.
Place the drill onto a work table. Insert the key into the keyed chuck. While holding the drill firmly against the table, tap the chuck key with a mallet, turning the chuck counterclockwise. Once the chuck breaks loose from the driveshaft, turn the chuck counterclockwise by hand to remove it.
Before beginning work on the drill, be sure that the drill is disconnected from the power outlet.