When you get new shears, or shears back from the sharpener, they are adjusted to cut. The adjustment for tension (or balance as some call it), is a screw or thumb wheel on the pivot of the shears. Beveled edge shears are adjusted to where the blades grab, about three-fourths of an inch from the tip. This enables the blades to slice from the pivot all the way to the tips. If tension isn’t set like this on beveled 10 inch shears, the blades may push apart from one another in thicker coat and fold at the tips. There is a space between the blades of beveled shears that has to be there, this gives the shear the “slicing” action it needs to get through tough coat with ease. This type of edge is the workhorse of the grooming industry and can be used on any type of coat. This edge lasts for months unless you drop them or hit something in the coat and create a nick.
Convex shears have a different edge all together. This edge is a razor, and is also sharpened differently. Convex edges are honed on both sides, first on the diamond wheel to create the edge, then honed on the interior of the blade to make that edge a razor. Convex shears have little or no space between the blades because they are so sharp they “chop” through hair, rather than slicing, to produce a beautiful cut used in finish work. Tension is adjusted to where the blades start to grab a third to half way down from the tips, keeping the blades as close as possible to each other. If the tension is too loose on a convex shear, two things can happen: the blades may grab three-fourths of an inch from the pivot creating a gouge, and they can fold hair at the tips.
Note: The tension adjustment is for adjusting the way the shear cuts, it’s not for the convenience or ease of the way the shear opens and closes. Tension can be adjusted a little, but if it’s adjusted so the shear feels loose to you because of hand or scissoring problems, that’s not good. There are shears available with ball bearings in the pivot. This type of shear feels loose no matter what the tension is adjusted at.
Clean your shears daily. Wipe all the hair from the inside of the blades, this attracts moisture which can rust your shears. If the blades have grime or hairspray on them, take a Handy Wipe and rub all this off. Never leave shears dirty because it will cause problems down the road.
Lubricate shears with shear lube only, it contains silicon and a light solvent. Not lubricating your shears can cause the screw to rust and not stay tight. There is moisture in your pivot from scissoring, lube gets rid of it. Not lubing can cause tiny pieces of hair and pet dander to remain in the pivot. This will tighten the tension, slow the shear down, and may cause a binding feel when scissoring. Lube the shear, then open and close them a few times to get the lube around the pivot. Convex shears need to be lubed more than beveled shears. Never use blade oil on a shear, it will stiffen over time.