Even perfectly sharpened blades can refuse to cut, and there are common culprits:
Detachable Clipper Blade Anatomy
Blade Set Adjustment
Most professional blades are interchangeable. The package or in the catalog will state that they are "A5" or "Snap On" type blades. Clippers commonly used by my clients are either Oster A5 or Andis AG, but interchangeable blades will also work on Wahl, Conair, or Laube.
There is a caveat however. If the blade is adjusted to work on an Andis clipper it may not work well on another clipper without some adjustment. To avoid frustration, if you use different clipper makes, you might keep the blades with the clipper you use them on, or even color code them.
You do not have to disassemble the blade to adjust the blade set. On the top of the clipper blade you will see little "ears" on the socket. The socket is attached to the comb by the two screws that go through the comb. The comb should never move when the clipper is turned on. If the little "ears are fitted properly, the comb will not "wiggle" or move from side to side. If the comb moves, even slightly, it will chatter, leave rows, pull hair, and bog down. The "ears" should fit snugly over the hinge assembly on (A5) and (AG) clippers. The hinge assembly differs slightly between companies. This difference will result in the blade set not fitting well, and this is why the blade set should be adjusted for each clipper. To adjust the blade; turn the clipper on (always do this first), mount the blade and observe if the comb has movement however slight. If there is movement, remove the blade and turn it over. Use very good slip-joint pliers, gently squeeze the "ears" together, and remember that a little goes a long way. Re-mount the blade and try it again. Repeat until all movement is gone. If you have closed the ears too much, they won’t mount. This can be remedied by forcing the ears over the hinge. While the clipper is running, place the back of the comb to the heel of your left hand and using your right hand, press hard enough with the clippers to force the blade into its proper place.
Sockets are notorious about suffering from metal fatigue. The ears are breakable. Don’t panic, sockets are cheap and easy to get.
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