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The Things We Carry

The Cutting Edge — Looking Sharp

By Tamia Nelson
tamia@paddling.net

February 24, 2004

A burly English knight, clad in steel plate and chain mail, stands in a tapestry-draped hall. An iron bar lies at his feet, its ends supported by wooden blocks. The knight raises a massive two-handed sword above his head. He pauses for a moment to gather his strength. Then he brings the heavy blade down with all the force at his command. A shower of sparks envelopes the bar. A deafening clang rings out through the hall. The point of the sword shatters a tile in the intricately inlaid floor.

And half of the iron bar lies on either side of the blade.

The knight grins broadly and steps back. After a moment's delay, his place is taken by a tall, slight man, dressed in a silk robe of magnificent richness. The tall man gestures. A cringing servant instantly scuttles forward to remove the two halves of the iron bar, leaving only a pillow in their place.

A second servant then hands the tall man a scimitar. It has a jeweled hilt, and the long, curved blade gleams in the light of the relentless Mediterranean sun, now streaming into the hall through high windows. The tall man extends his sword arm. With infinite care, he places the edge of the scimitar on the pillow, then draws the blade gently toward him. A cut like the mouth of an open wound blossoms in the pillow's white silk cover, exposing a dark red lining. Making no more sound than the wind makes in parting the reeds along the river, the curved blade speeds downward through the unresisting silk, slicing the pillow in two. A cloud of feathers explodes into the air.

The tall, slight man stops his blade's descent just as it reaches the final thickness of fabric. He hands the scimitar back to the servant, then inclines his head slightly in the direction of the English knight. The merest hint of a smile plays across his lips.

The mail-clad knight does not return the bow. All the blood has drained from his face. Wordlessly, he wheels around and stamps out of the hall.

 

If this sounds like a scene drawn from a nineteenth-century romantic novel, that's because it is. But the two men were real enough. The English knight was Richard Cœur de Lion, king of England; the tall man, Salah el-Din, sultan of Egypt and Syria. They were enemies, and their armies met in the Holy Land late in the twelfth century. The echoes of their conflict can still be heard today.

But that, as they say, is history. And whatever their differences on and off the field of battle, it's a good bet that both of these men knew all there was to know about obtaining — and maintaining — a cutting edge. Fortunately, their hard-won knowledge hasn't been lost. Now that you've got a knife of your own, let's see how to get it sharp and keep it that way. After all…

A Dull Knife is a Dangerous Knife.

Dull blades slip. Dull blades gouge. Dull blades don't go where you want them to go. A dull knife is an accident waiting to happen — to you, or to someone you care about. So you'll have to master the art of sharpening sooner or later. Probably sooner. Not many knives are ready to use right out of the box. Despite this, many of us are a little afraid to sharpen a blade. We're scared that we'll get it wrong. Or cut ourselves. Or maybe we just don't want to take the time. None of which makes any sense. This is one art that anyone can master. All it takes is a little patience, a modest amount of practice, and a dollop of prudence. Here's how it's done.

First things first. Leave the grinding wheels and power grinders to machinists, locksmiths, and master cutlers. You don't need a power assist. A knife is a hand tool, and you can sharpen it by hand, using only a whetstone and steel. Of course, you can also purchase a proprietary "sharpening system" if you're so inclined. Both the process and the end result are essentially the same. Whether you're sharpening a pen-knife or a broadsword, you do it by grinding away tiny amounts of metal, then honing the resulting edge to remove any burrs. That's all there is to it. The factory grinding (the "primary bevel") sets the stage. If an edge is comparatively blunt, it will be durable but not necessarily keen — ideal for hacking and chopping. Remember Richard Cœur de Lion's broadsword? It had a blunt, cold-chisel-like edge, just what was needed for smashing through chain mail and severing iron bars. On the other hand, if a blade has a shallow, tapered bevel, the resulting edge can be made razor sharp. It will also be delicate, however, and much more easily damaged than its blunter cousin. Best to reserve it for slicing and other fine work. Salah el-Din's scimitar had such a blade.

The primary bevel on the edge of your knife will almost certainly be a compromise, neither a cold chisel nor a razor. Unless you want to regrind the blade to another bevel — a touchy and time-consuming job, this is best left to a master cutler — you'll need to work with the factory edge. You have two choices here. You can simply follow the factory bevel when you sharpen your blade, or you can steepen the angle slightly at the cutting edge, creating a blunter secondary bevel. The first course is often called parallel honing. It will yield a sharper edge, but it also requires that you retouch the entire bevel each time you sharpen your knife. The second alternative is one that will be familiar to most woodworkers who own a battery of planes and chisels. Its advantage? A slightly more durable edge, and one that's a bit easier to retouch.

Before making up your mind which course to follow, get acquainted with your knife. Examine the edge closely in bright light, rocking it from side to side to get the best possible view. Identify the primary bevel. If it lies close to the working edge — this is the case on many utility knives — you won't want to steepen it further. Parallel honing is the way to go here. But if the primary bevel is shallow and extends back from the edge a quarter inch or more, as is often the case on "survival knives," you may want to create a steeper and blunter secondary bevel.

Once you've come to a decision, assemble your tools. Connoisseurs will use nothing but quarried stone, ranging from soft, coarse Washita to fine-grained hard black Arkansas. Pragmatists will get by with whatever the local hardware store has on sale. I've flirted with both extremes, and I've come to the conclusion that any flat stone with a uniform grain is good enough. It helps to have a choice of grits, though. The coarsest stones feel noticeably gritty to the touch. These are best reserved for regrinding damaged edges. By contrast, the smoothest stones have no apparent grain or grit. They're ideal for honing edges that are already sharp. A steel — a tapered rod, traditionally formed from hard steel, but now also made from ceramic and even glass — is also worth having, though you'll seldom see one outside a foodie's kitchen, unless it's in the tool roll of a professional chef.

What do you really need? A Carborundum® combination stone from the hardware store with both medium and fine grits makes an excellent starter. And while a pocket stone is handy for touch-ups in the field, when you get back home bigger is better. My workhorse stone measures three inches by twelve.

Prepare your medium-grit stone by spreading a film of light oil on the surface. Mineral oil is recommended for most stones, but I use corn oil on my kitchen stone. In the field I use spit. Both work fine for me. If you're not inclined to experiment, however, just follow the recommendations of the manufacturer. (Some stones — Japanese waterstones, for example — are intended to be used with water as the only lubricant.)

After you've oiled your stone, you're ready to begin. Orient the stone so that the long axis points away from you. Then place the heel of your blade on the stone at the end nearest you. Next, raise the back of the blade until the primary bevel makes uniform contact with the stone's surface. (I'm assuming that you do not intend to create a secondary bevel.) The 20-degree bevel typical of many knives will require that you raise the back of a one-inch-wide blade about one-third of an inch. Narrower blades require proportionally less elevation. Wider blades require proportionally more. Don't get your ruler and protractor out, though. Just look at how the edge makes contact with the stone and be guided accordingly. (A magnifier can be a big help here, particularly if your eyes aren't as young as they once were.)

The Cutting Edge

When you're satisfied that you've got the angle right, push the blade away from you, applying moderate pressure and moving the edge across the stone from heel to tip as you go. It's just as if you intended to slice a sliver from the surface of the stone. You may find it helpful to place a fingertip on the back of the blade to keep the edge properly aligned. Use your other hand if necessary. There's no hurry. Work slowly and carefully. When you reach the tip, lift the blade off the stone, return to the starting position, and repeat. Do this six to twelve times.

Now turn the blade over and work on the reverse of the bevel. This will require that you hold the knife in your other hand. If that seems impossibly awkward, you can simply keep your grip but change direction, pulling the reversed blade toward you rather than pushing it away. Whichever method you adopt, though, it's important that the number of repetitions be the same on both sides — and that you always hold the angle constant. Emerson ("A foolish consistency is the hobgoblin of little minds") was wrong, at least in this instance. He probably paid someone else to sharpen his knives.

After one set of repetitions on each side, test the blade, cutting down against the edge of a sheet of writing paper. A sharp blade will cut clean. A dull blade will only crease the paper or nibble at its edge. (Old hands often test a blade by running their fingertips lightly over the cutting edge. If you're tempted to follow their example, be careful. Many old hands also have scarred fingertips.) Don't expect that one set of repetitions will be enough. Repeat until you're satisfied that the edge is as sharp as it's going to get.

Now is the time to bring your fine-grit stone into play. Oil the stone and then begin as before, though with slightly less pressure on the blade. Six to twelve strokes on one side. The same on the other. Test. Repeat. Test. At some point, your edge will glide down through paper like Salah el-Din's sword through the pillow. When this happens, you're nearly finished. There's just one thing left to do.

A newly-sharpened blade often develops a "wire edge," a nearly invisible burr. This burr can be removed by sweeping the edge over a steel from heel to tip, holding it at the same angle as in sharpening. A chef steels his blades downward, toward his hand, alternating sides with each stroke as if he were cutting slices from each side of the steel. Sweep follows sweep with lightning speed. It's an impressive performance, to be sure, and most steels have a cross-guard hilt to minimize the likelihood of injury. But accidents still happen, and cuts on the hand can be nasty things. You may prefer to steel your blades by pushing them away from you, instead. It's less cinematic, but much safer. Just remember to alternate sides. You'll also find that steeling can restore a blade's edge between sharpenings. When a few sweeps along the steel no longer do the trick it's time to get out your whetstones again.

But what if you don't have a steel? No problem. Pulling your newly honed blade back across your fine-grit stone will do much the same job. It's the reverse of the sharpening process. You're not "shaving" the stone now. You're smoothing the cutting edge of your blade. Use a light pressure, hold the angle constant, and be sure to alternate sides.

Serrated edges present special difficulties. Some sharpening systems claim to make the job of restoring dulled serrations easy. I can't say if they do, though. I've never used one. I have succeeded in sharpening serrated edges on a stone, however. But only when the serrations were "single-cut" — when the cutting edge lay along the reverse of the blade, rather than on the mid-line. (Single-cut edges are common on cheaper serrated knives.) Then I just hone the reverse edge on the original bevel. And what if your serrated blade isn't so accommodating? It's likely that a tapered slipstone can be used to sharpen even twice-cut serrations. I'll have to try it some day.

The world has changed almost beyond recognition since Richard Cœur de Lion and Salah el-Din met to match swords. Edged tools are still with us, though, and so long as we depend on them, we owe it to ourselves to keep them looking sharp. That's cutting-edge technology at its best.

Next month, Tamia describes how to make your favorite knives last almost forever — and how to insure that they seldom bite the hand that holds them.

Copyright 2004 by Verloren Hoop Productions. All rights reserved.
















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