There are several types of hair clippers on the market today. Some have two-piece blades and some have interchangeable blades of varying sizes (Reference 1, 2, 3, 4). Hair clippers are a staple tool of most hairdressers and barbers and with time and use their blades will go dull. It is not necessary to purchase a new set of clippers when this happens. You just need a new blade, some effort and a little know how to get your clippers cutting again.
Unplug the clipper and hold it in your hands.
Place your fingers on the cutting edge of the blade and press it inward toward the rear of the clipper. Lift the blade upward and off the clipper machine (Reference 3).
Clean any hair or residue from the open clipper case with your brush. Blow air into the open case to clear out any remaining bits unreachable by your brush (Reference 5).
Align the new blade in the slot from which the old blade came. Press the blade toward the back of the clipper and compress the blade set spring (Reference 3).
Press the blade downward and into the clipper body until it reaches the normal position. Release the blade and allow it to slide into the locked position (Reference 3).
Unplug your clippers to ensure that there is no danger of electric shock while working on them (Reference 1). Unscrew the old clipper blades with your Phillips head screwdriver. Locate the two set screws along the bottom of the clipper blades farthest from the cutting end. Insert the screwdriver and turn to the left until the screw releases completely. Repeat this process with the second screw (Reference 2).
Remove the outer blade by lifting upward and away from the clipper body. Inside you should find the smaller cutting blade floating on a plastic guide located between the blade shell and the clipper body (Reference 2).
Sweep away any hair or residue from inside the clipper or around the blade area using your brush. Blow air into the open chamber to clear out any additional particles which may not be accessible with your brush (Reference 5).
Install your new inner blade by laying it into position on the plastic guide with the plastic bump set into the corresponding notch on the inner blade. Align the screw holes in the outer blade with the screw holes in the clipper body. Insert one set screw and tighten most of the way with your screwdriver. Insert the other set screw and tighten most of the way (Reference 2). Leave some play in the set screws to allow for blade adjustment and proper alignment prior to locking them in place.
Make sure the clipper blades are level with each other and the clipper body so the cut they make is straight (Reference 2). Tighten the set screws completely. Squeeze a few drops of clipper oil into the blades at the top and between the blades along both sides. Allow the oil to seep in for a few moments (Reference 5).
Plug in and turn on the clipper and allow the oil to work through the blades for 20 seconds or so. You should hear a difference in the sound that the clipper makes as the oil works its way through. The sound will change from tinny and metallic to smooth and quiet. Wipe away any excess oil from the surfaces of the clipper and blades with your rag (Reference 5).
A third type of clipper blade exists which requires you to press a release button at the rear of the blade to remove. To insert a new blade, angle the cutting end of the blade into the front of the clipper. Press the rear of the blade down and into the locked position on the clipper (Reference 4).
Make sure never to use your clipper near running water or an open toilet or tub with water in it. Electric current and water do not mix and can cause injury (Reference 5).