Scissors & Shears

Scissors & Shears

Want to know how scissors are sharpened and adjusted, read below.

For sharpening prices see the Price List tab on left: Most scissor sharpening runs between $8-15.00.

For sending to Bruce's Sharpening

PO Box 41, Maxatawny, PA 19538 by USPS mail

For UPS or FedEx use 15868 Kutztown Road instead of the PO Box.

Proper scissor sharpening is more than grinding a new edge. A scissors inside line must also be even from tip to pivot or a scissor will not cut evenly from pivot to tip. A scissor should have proper "SET" (the curve of the blades) be properly "BALANCED" (the "fall -how it closes"), and the tips should close but not gap or overlap past the cutting edge. Scissor screws should not loosen with use and finger rests, finger/sizing rings and bumpers (also called silencers) should be firmly attached and not damaged. Scissors are sharpened at Bruce's Sharpening using diamond or CBN wheels starting with a coarse wheel if needed to remove heavy nicks or other damage, then a fine wheel and finally polished to a burr free edge. The inside line is honed with fine diamond to ensure a smooth ride and evenness of cut. Often even named branded scissor fail to have a uniform even inside ride line from pivot to tip and if not corrected a scissor with a bad ride line will not cut end to end well or at all.

Scissors are cleaned, sharpened, balanced (fall adjusted - tension) and set (curvature). Missing parts like scissor bumpers and washers are added or replaced. Each scissor is tested and adjusted until it cuts cleanly end to end with special materials sensitive to folding or shreading, then tested in hair to ensure it will cut what you cut. How long a scissor will stay sharp depends on how clean the hair is that you cut, dirty hair can dull a scissor edge pretty quickly. Other factors are the quality of the steel and frequency of use. Dropping a scissor can result in nicks in an edge or bending of a blade. Either or both will cause the scissor to stop cutting and the edge and set will have to be redone. A rubberized floor can help minimized damage. Convex edge scissors with their acute angle edges will dull quicker than a bevel edge scissor.

The Term "Shear" orginally identified large scissors such as carpet shears and other large scissors used for heavy duty applications. As specialized scissors were developed for the hair stylist as opposed to a "barber" the term "shear" was adopted by stylists to differentiate the different kind of cutting that a stylist does over the old fashioned barber-pole hair cutting shops. Call them what you will, they all are designed to cut hair.

There are three basic factors which affect how well a scissor will cut. Sharpness of the edge, the amount of set (curvature) of the two blades and the inside hone line. Many well-known brand name scissors can have one or more of these 3 necessary factors that are less than ideal. Cheap scissor can have 2 or more! Any scissor won’t cut optimally until the flawed condition is corrected.

Scissors are manufactured by starting with a soft metal and doing the basic shaping. Once the scissor final shape has been obtained the metal is then hardened by heating it to a high temperature. The temperature will vary by the type of metal. The scissor then is quenched (rapid cooling). This process changes the internal metal structure and makes the metal very hard. If left in this hard state the metal would not bend and be brittle. The metal is then softened a bit with a process called “tempering.” This is done by heating the metal again but to a lower temperature and allowing it to cool from that temperature. The tempering leaves the metal still quite hard but gives it flexibility. For forged scissors this is the basic process. Cast scissors are made by pouring metal into a mold and they will not have the hardness or flexibility for most grooming and salon work. You will most likely find cast scissors in your kitchen junk drawer, not in a salon or grooming shop.

The blades of a scissor are curved toward each other called “set.” This set acts much like the spring on a clipper blade which keeps the cutter teeth against the comb teeth. Without enough set (tension) the hair in a clipper blade would get between the cutter and comb teeth and cutting would stop. Similarly the set of a scissor is necessary to apply enough pressure as the scissor is closed so that hair will cut between the scissor blade edges and not fold. This lack of sufficient set most often shows up near the tips of scissors where hair simply folds rather than cuts. The blades then have to be re-curved until the scissor again cuts without folding the hair. Dropping, stepping on, or just trying to cut too much hair with a dull scissor edge can cause the set to change. If the scissor set is lost and has to be added a scissor bender is used. Some use a hammer and a curved anvil but this is mostly done in Japan to add set to a scissor blade. If the scissors have not been tempered properly or if there are flaws in the metal a scissor may break during setting. This is unfortunately but it’s a manufacturing issue that doesn’t show up too often but can happen. Most manufactures will not warrant their scissor against breakage unless they are the ones to break them. Then they simply replace them and you won’t know about it. If you use a local sharpener and not the factory this is a risk you will have to take but as I wrote, it is very rare.

The other factor that affects the cutting quality is the inside line of the scissor which should be even from heel to tip but often in lower quality scissors there are low spots which can make a scissor cut unevenly at best or not cut at all in certain locations. This can be corrected by your sharpener. Better made scissors have properly honed inside scissor blade faces. So it is not only how sharp the edge is but how uniform the scissor blade face is and the proper set to make a scissor cut hair easily.

You can left click or touch on tablet or phone on the images below and elsewhere to get a larger image.

These scissor grinders are made by Wolff Industries and can handle every kind of scissor. Convex edge scissors are ground with 800 grit diamond wheels and then highly polished. Bevel edge scissors are ground with 400 grit diamond wheels and polished. Special diamond/ CBN or ceramic hones are used to establish the "inside line" on hollow ground convex edge scissors. In the picture are also a handle bender, scissor set tool, an anvil for tightening riveted scissors and scissor pliers for loosing and tightening frozen screws. I stock screws, bumpers, finger rests and finger rings.

Typical grooming scissors

Replacement sizers or comfort rings

Replacement Bumpers, Screws, Washers

$12 set replacement shear blades

Flat hone versus "grinding"

This is an interesting topic for those who have been told that one or the other is a better method to sharpen shears/scissors.
Know this. Your cutting edge doesn't care!
For convex edge scissors the convex shape requires much more work than a bevel edge, but the only part that cuts hair is the edge, not the convex shape behind it. Special convexing scissor holders allow "grinders" to convex shape the scissor, just like the flat honers who have to have hand roll the scissor on the spinning disc to get a convex edge. How good their hand motions are determines how well they can sharpen a convex scissor. The convexing jig on a grinder insures repeatability each time the scissor is sharpened. Some of the newer flat hone machines have developed special clamps that can eliminate some of the operator skill.
A grinder uses a circular abrasive wheel to "grind" away the dulled portion of your scissors. In my case it is a series of finer grits from coarse to fine. A flat hone uses flat circular discs of what is basically sandpaper to abrade (grind) away the dulled portions of your scissors. Like I wrote - your scissor edge doesn't care how it became sharp again. Flat honing tends to take longer than using a grinding wheel, that's why flat honers charge much higher prices and to justify their higher prices and tell you about how flat honing is so much better. A flat honer goes from coarse sandpaper discs to fine with each finer grit taking out the scratches from the previous grit and then polishes the edge as a final step.
Convex edge scissors use a much finer angle - typically 40-50 degrees - while bevel edge scissors are typically 25-35 degrees. The finer edge is polished too because it looks pretty and gives the thin edge a bit longer life than an unpolished edge. The thinner the edge, the quicker the edge will dull so polishing helps get that razor cut edge a bit more life than it would have otherwise.
Convex and bevel edge scissors need the "inside line" be maintained by honing this area of the scissor. Scissors have to be taken apart so the inside line can be honed from past the pivot point to the tip. This has to be done properly in order for the edge to cut, just sharpening the outer edge isn't enough. One of the big issues with uneven inside line is the loss of tension if there is a low spot. The tip area will be very weak if the pivot area is low, something I see from too many manufacturers these days. If your tips fold the hair instead of cutting the pivot area is probably lower than the blade length and needs to be fixed.
Each method gets to the same end. The skill and knowledge of the operator is key to getting the best cutting edge regardless of the method.