GET THE ANGLE ON KNIFE SHARPENING
It’s the angle.
That’s the gist of a conversation I had with a knife-sharpening expert. I’d been having trouble honing one of my favorite knives and was explaining my sharpening process. It’s all in the angle, he said. Get the angle right, and be consistent on the angle and you can sharpen any knife, he said.
He went on. Knives come sharpened at various angles and it’s best to sharpen them at the same angle, following the angle ground onto the blade by the manufacturer. Otherwise, you’re fighting against the original edge.
The catch is, different manufacturers use different angles, but hunting knives and pocketknives usually come with angles from 15 to 25 degrees. You can start quite a discussion on blade angles by throwing out suggested degrees, so take this with a grain of salt. That said, filet knives tend to have sharper angles, perhaps 12-15 degrees. The less angle, the sharper the blade, but also the less durable the edge. That’s why heavy chopping blades, such as axes and hatchets, have a more durable angle around 30 degrees.
There are a host of sharpening systems and methods, some of which help you hold your blade at a consistent angle, but everyone should know the basics of knife sharpening with just a stone.
But before we begin, we should look at two popular types of stone sharpeners – diamond and natural stone. Diamond stone sharpeners usually consist of a layer of tiny micron-sized diamonds bonded to a flat metal surface. The unparalleled hardness of diamonds creates an aggressive sharpening surface, meaning not a lot of pressure is necessary during sharpening. Natural stones, usually called Arkansas stones because good quality stones are mined there, come in different grits, from coarse, for aggressive sharpening of dull blades, to fine for finish honing.
To touch up a blade that is not extremely dull to, for instance, restore a fine edge prior to field dressing, use a medium- or fine-grit stone – diamond or natural. If the blade is really dull through use or abuse, start with a coarse-grit stone to restore the edge quickly, then switch to a medium-grit stone, then if you are looking for shaving sharp, to a fine stone to finish.
A final thing about stones before we get into the sharpening process. Stones should be dampened to lubricate the surface and float metal filings and other contaminants so they can be wiped away, preventing buildup that could affect abrasiveness. Some say diamond stones can be used dry, that their abrasiveness is not likely to be hampered but if you plan to use a dampener, use water not oil. For natural stones you can use water or oil, though once you use oil water will no longer be effective. I prefer oil anyway. The best advice is to follow the sharpener manufacturer’s directions.
OK, on to sharpening.
Placing the sharpener on a flat surface will help you hold a consistent angle. If you hold the sharpener in one hand and blade in the other, you have two moving surfaces that need to align at the proper angle. Setting the sharpener on the table takes one variable out of the equation.
With the sharpener ready, place the blade flat on the sharpening surface, then slightly lift the back of the blade until the beveled edge of the blade aligns with the stone. The blade will be scratched during the sharpening process. From the scratches you can determine if you are holding the blade at too high or too low of an angle. If you have trouble matching the blade’s original angle or it is difficult to determine, try lifting the back of the blade about the width of the blade.
Holding the blade at a consistent angle, stroke the blade across the sharpener as though trying to shave a thin slice from the stone, applying gentle pressure. Too much pressure is not a good thing. It is better to work slowly and gently. During the stroke, move the blade from the hilt to the tip (or vice versa), maintaining slight pressure and proper angle throughout the stroke.
You can also sharpen with a circular motion, again working from hilt to tip with even pressure, angle and control. Just keep the blade on the surface and use a slow clockwise circular motion with the edge facing to the right; when you turn the blade over, switch to a counterclockwise circular motion with the edge facing the left.
No matter the method, straight-line stroke or circular, alternate sides after 10 to 15 strokes, then repeat the number of strokes on the other side. Keep it even.
As mentioned earlier, if our knife is very dull, start with a coarse stone and once you’ve honed a decent edge, switch to a medium or fine stone to finish. A medium stone will usually produce a workable, sharp edge. Fine stones can put finishing touches on filet knives and other blades needing a keen edge.
There are a number of knife-sharpening systems out there that will take some of the guesswork out of the process. Lansky sharpeners (lansky.com), for instance, clamp the blade and hold the stone at your choice of angle. WorkSharp (worksharptools.com) has a nice pocket sharpener with 20- and 25-degree guides to get you started across the stone at the correct angle. Spyderco’s Tri-Angle Sharpmaker (spyderco.com) holds sharpening rods at an angle so you can stroke your blade across them. And I carry an Eze-Lap diamond stone (eze-lap.com) in my hunting kit for in-the-field touch-ups. I also like Smith’s (smithproducts.com) two-step pull-through sharpener with coarse carbide blades on one side and fine ceramic rods on the other, all pre-set at sharpening angles so all you do is draw your blade through the appropriate notch. I also have Smith’s oval diamond sharpening rod in a kitchen drawer to keep cooking knives in tip-top shape.
Chef’s Choice (chefschoice.com) makes electric sharpeners that simplify sharpening tasks. (But don’t sharpen a knife on an electric workshop grinding wheel. They are too aggressive and can overheat the blade and ruin the temper of the steel, creating a brittle and nearly worthless edge.)
There is a whole world of sharpening out there, numerous products and techniques for different types of blades. Many of these manufacturers will provide sharpening tips to cover about every situation, and they have a variety of quality products to make your sharpening efforts a keen experience.
Knife sharpening is a useful skill for hunters, plus it provides a sense of satisfaction when your sharp knife makes short work of the task at hand.