How to Sharpen Knives and Scissors

Super-sharp results in less than 5 minutes

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Remember the last time you sliced a tomato and it looked like it had been cut with a spoon? Well, say goodbye to dull knives and scissors and make your everyday kitchen and office chores a breeze. In this article, we'll show you several sharpening jigs and stones you can buy and how to use them to get razor-sharp results even if you've never sharpened a knife in your life. There's a whole discipline of sharpening knives, but we've distilled this information to just the essentials so you can get back to thinly sliced tomatoes and on to dinner.

Sharp edges from an inexpensive tungsten sharpener

The first time I tried one of these little sharpening tools, I couldn't believe how well it sharpened dull kitchen knives. They're designed for knives that still have their factory edge intact without nicks or irregularities—knives gradually dulled from everyday use.

The tool has two opposing tungsten steel sharpeners at fixed angles to remove metal and sharpen the edge as you pull it from the base of the blade to the tip. You can buy an inexpensive model and it'll do a respectable job of sharpening most kitchen knives. But the small, preset angle of these sharpeners makes them less effective on more blunt edges, like those on butcher knives. These knives have a fatter blade and wider angle. For this type of job, you'll need to use a traditional sharpening stone.


Your fingers are every bit as delicate as the meat and vegetables you're cutting—be careful when sharpening!

Restore an edge with a precision system

The precision blade-sharpening system shown here is great for restoring an edge because it's nearly impossible to make a mistake. In fact, to ruin a knife you have to try to use the system incorrectly. The system comes with three stones: a coarse synthetic stone for restoring an edge, a medium triangle blade for serrated knives, and a fine Arkansas stone for finishing and fine sharpening. Variations of this sharpener with even more angle and stone options are available from other manufacturers.

To use this system, just clamp your knife blade into the jig's jaw with the edge facing out. The guide rod keeps the attached stone at the proper angle as you push it across the blade (lower guide slot for kitchen knives and upper slot for hunting knives). The first time you sharpen a knife with this jig, use the coarse stone to restore the angle and then use the fine stone. On subsequent sharpenings, you'll most likely only need to use the fine stone.

Serrated knives are tough to sharpen and require a great deal of patience and attention to detail. To use the triangular stone in this kit, clamp the knife into position and move the stone up and down across each serration of the blade. Don't try to grind the whole semicircle of each serration; just move the stone across the center of the trough several times. Work your way from one serration to the next. Most serrated knives only need to be sharpened on one side, since the back of the blade is usually flat.

Match the exact angle with a sharpening stone

You can't always match blade angles with jigs, so if you want an exact match, use the traditional sharpening technique with a sharpening stone. Once you get the hang of it, the initial anxiety of using this method quickly fades. Practice on a knife that you're not particularly fond of. You can buy individual stones, or you can get an inexpensive synthetic stone with a medium grit on one side and a fine grit on the other that'll handle most sharpening jobs. Our stone sharpening device (Photos 1 and 2) had three stones built in (coarse, medium and fine) and will handle any type of knife. The coarse stone is only needed for serious edge restoration.

The condition of the knife's edge will determine what grit of stone you should use. If you have nicks or irregularities from previous other bad sharpening jobs, start with a coarse grit and move to medium and then to fine grit. If your knife is just dull from use, you'll only need the fine stone.

Keeping Your Sharpening Stones in Good Shape

After several sharpenings, your stone will start to clog or get dished even if you've tried to use the whole surface of the stone while sharpening. The best way to unclog your stone is to put it into a bucket of soapy water and scrub it with a stiff nylon brush. To resurface the stone to its original flatness, wet it down and scrub it on top of a concrete block. After several passes, sight down the top and check it for flatness. Another method is to tape a silicon carbide sanding belt to the underside of a thick piece of glass and push the sanding belt back and forth across the stone until it's flat. With either method, it will take longer with synthetic stones than with natural stones.

Ceramic sharpening rods are fast and accurate

This system is a great, 20-second method for sharpening knives that are in relatively good shape. The ceramic-coated steel bars are tipped at a 20-degree angle so all you need to do is hold your blade steady at a 90-degree angle to the base of the sharpener. Several passes on each rod to do both sides of the blade will renew a keen edge. No lubricant is required for this sharpener, since most of the residue from the blade falls to the work surface. Occasional cleaning with a nylon brush and soapy water will keep the ceramic grit from clogging. This model folds flat for easy storage.

Keep your sharp knives sharp with a chef's steel

No doubt you've seen these used in old cartoons depicting a wolf sharpening his cutlery as he contemplates his rabbit stew. These tools help keep a sharp knife sharp by holding the fine edge straight and removing any tiny imperfections in an edge. A chef's steel will reduce the need for sharpening, but you'll eventually have to hone a new edge with one of the other sharpening devices we've shown you.

Using a chef's steel in the characteristic freehand style takes skill and a feel for the edge of the knife. But you can still get great results and take most of the guesswork out of these sharpening aids by planting the top of the steel perpendicular to the table. Next, hold the base of the knife against the top of the steel (usually about 15 degrees to the steel). Pull the knife down and back toward you until the tip ends up near the bottom. No need to apply a lot of pressure. Again, smooth, even pressure is all you need, just like when you're cutting an apple with a sharp knife. Alternate sides of the knife, making sure the whole edge contacts the steel as you pull.

Scissors sharpening with simple sharpening jigs

Sharpening scissors with a sharpening stone is tough work, but these two jigs make the whole process nearly foolproof. You'll find that both of these jigs will do a great job, although the sharpener in Photo 1 requires a bit more finesse. This sharpener needs to be held precisely at the angle of the blade while the tungsten bar in the sharpener scrapes the steel along the whole edge as you draw it toward you. You must keep the entire tungsten bar in contact with the edge as you firmly pull it from the base of the blade to the tip. About five passes should do the trick. When one side is shiny and completely flat and smooth, the blade is sharp. Flip the scissors over and repeat the process for the other blade.

The sharpener in Photo 2 is self-adjusting. It'll sharpen left-handed scissors in one side and right-handed in the other. It has a ceramic bar that floats between the blades and automatically sets itself to the correct angle as you gently squeeze the scissors and pull or push it through the opening. Don't push hard; just pretend you're lightly cutting a piece of paper and maintain consistent pressure. A few passes and your scissors should be sharp.