At some point in every knife enthusiast’s ownership, that trusty blade will lose its touch. Maybe it’s sliding in place or maybe it’s requiring a bit more effort; whatever the case may be, if your knife isn’t cutting quite the same, it’s time to give it a good sharpening. Because the fact is, a dull knife is a dangerous knife, as the added force needed to slice inherently puts your fingers in harm’s way. With just one wrong move, you’ll be headed to the ER faster than you can say “oops.”
Now, we’re not saying this in an effort to scare you, but rather to emphasize the importance of proper blade upkeep. In addition to making your cutting endeavors considerably more efficient, sharp knives are also exponentially safer. Accordingly, we’ve put together this handy beginner’s guide on how to sharpen knives on a set of whetstones. But first, let’s talk theory.
Video: How To Sharpen A Knife On A Whetstone
Sharpening a knife on a whetstone is a highly nuanced procedure that’s best portrayed through video. Check out the accompanying step-by-step knife sharpening guide over on our YouTube channel.
Knife Sharpening 101
The Theory Behind Using Whetstones
Before you break out the whetstones or start taking your knife to a strop, it’s important to understand what the objective is when sharpening: removing material from the blade’s edge (the bevel), using an abrasive (your whetstones) to shave off excess material and set a new cutting surface.
You do this by making passes on each side of the knife and raising a fine layer of metal that’s known as a burr. As you alternate sides, you’ll continue to fold the burr back and forth, gradually breaking it loose and revealing the fresh edge. Throughout the process, you’ll work your way down from a coarser abrasive to a finer one in order to whittle away the burr. From there, it’s helpful to use something called a strop so that you can really hone a razor-sharp edge.
Equipping Yourself For Success
Whetstones: When sharpening your knife according to this method, you’ll — obviously — need a set of whetstones to use as an abrasive. If your knife is chipped, or it’s been some time since your last sharpening, go for something rougher like a 500-grit. For routine maintenance, however, 1000- and 5000-grit stones should suffice.
Water: You’ll also need a way to coat your stone with water. A bowl works just fine, but we like spray bottles since they make application fast, easy, and mess-free.
Angle Guides: Because sharpening is all about finding the correct angle of your bevel, it helps to have a set of guides to get you off on the right foot. As you gain more practice sharpening and get more comfortable with the process, you’ll learn to determine your angle by feel.
Permanent Marker: By the same token, we also suggest blacking out your bevel with a permanent marker.
Cleaning Cloths: Try as you might, sharpening can be a pretty messy process, so you’ll want to keep some paper towels or microfiber cloths handy.
Strop: If you’re really after some next-level sharpness, we’d suggest two optional pieces of equipment: a strop and a cork. It’s entirely possible to sharpen a knife from start to finish on a single stone, but the strop helps you hone your edge, and the cork removes any traces of burr that might be left behind.
Knife: Last, but certainly not least, you’ll need, of course, your knife. Be sure to give the blade a good clean before attempting to sharpen.
Keeping An Eye On Your Progress
The Permanent Marker Trick
Step 1: Begin by applying a layer of permanent marker to each side of the edge’s bevel. Doing so allows you to get a quick visual cue as to whether or not you’re sharpening at the correct angle. Don’t worry — a quick wipe with some rubbing alcohol will have any excess marker gone and your knife looking good as new.
Step 2: Next, you should prep your first whetstone by coating it with water. Attempting to sharpen dry will clog up the pores in the stone’s surface and make it considerably harder to raise that edge burr. When applying water, there’s no need to overthink it — just be sure to do so evenly and to do so often.
Making Your First Passes
The 1000-Grit Whetstone
Step 3: With your knife gripped in your dominant hand, you should now determine the angle along which you’ll be sharpening the edge. If you’re not confident in your ability to find the edge’s bevel, you can use an angle guide to check your progress.
It’s important to note that bevel angle varies from blade to blade, with pocket folders falling around 17° and kitchen knives coming in about 20°. You’ll also want to line up the tip of the blade at a 45° angle to the edge of the stone, using your other hand to provide pressure as you make complete strokes.
Tip: When sharpening your knife, be sure to grip the handle with three fingers and use your thumb and forefinger for support along the blade.
Step 4: After you’ve determined your bevel angle, remove the guide and begin to make some strokes on the first side of your knife. You should only be applying pressure on the trailing strokes, or those with the edge following the spine of the blade; doing so on your leading strokes (those with the edge in front) will damage your stone.
Once you’ve made a couple of strokes on your whetstone, check the bevel to confirm that you’re sharpening at the correct angle. If you’re doing it right, you’ll only have removed the marker along the bevel. Too low, and you’ll have worn away the marker above the knife’s edge. Too high, and it’ll look spotty and inconsistent from heel to tip.
Tip: Avoid cleaning your whetstone as you work on your knife. Throughout the process, a layer of gritty metal filings — known as a slurry — will build up on its surface and assist in your efforts to raise a burr.
Step 5: When you’re comfortable with your sharpening angle, continue making complete passes from heel to tip, working the knife down with one hand while applying even pressure with the other. Be sure to follow the curve of the blade as much as you can here. When nearing the tip, you may need to adjust your arm position and lift the handle slightly in order to hit every part of the knife.
As a general rule of thumb, we’d suggest starting with anywhere between five to ten full-length passes, though it’s really down to how much maintenance your knife requires. In any case, once you’ve made a couple of passes, check for a burr. You can do so by running the edge of the blade across the top of your thumbnail, feeling for any rough spots or resistance.
Step 6: When you’re ready to tackle the other side of the blade, apply some fresh water to your whetstone and pass the knife to your other hand. As before, you’ll want to make a couple of initial strokes and then check your edge to verify that you’re working at the right angle. Once you’re happy with your results, repeat Steps 2-5.
Polishing Things Up
The 5000-Grit Whetstone
Step 7: After you’re finished making passes on your 1000-grit whetstone, wipe down your blade and reapply some permanent marker. Because finer-grit stones don’t provide quite as much feedback, you’ll want this for visual evidence that you’re still sharpening at the correct angle.
Step 8: As with the first stone, you should lightly spritz your 5000-grit whetstone with a bit of water.
Now that you’ve had a chance to make some passes on the knife, you’ll probably be able to determine your bevel angle by feel. If not, grab your guide once again and confirm that the blade is positioned properly before proceeding. You want to stay consistent from stone to stone, so it’s always a good idea to double-check just to be sure.
As before, you’ll want to line up the edge of the knife at its respective angle, position your arm at 45° to the edge of the stone, and make complete strokes from heel to tip. With finer-grit stones, it’s best to start with around three to five passes per side. Because they aren’t nearly as abrasive, it may be harder to detect a burr; check your knife early and often against your thumbnail, feeling for inconsistencies and any resistance.
Honing Your Edge
The Strop And Cork
Step 9: Stropping the blade’s edge is the last major step in our knife honing process. We generally like using a leather strop, but you’re more than capable of doing so on a whetstone as well. In keeping with your previous passes, you’ll want to maintain the same sharpening angle. Now, however, you’ll only be moving the knife from tip to heel — not making perpendicular strokes.
Tip: Because it’s a much more delicate procedure, you want to stay conservative with your stropping. Start with 3-4 passes per side, gradually decreasing your number until you’re making a single pass with each hand.
Step 10: Still not satisfied? If you’re really looking for that razor-sharp edge, there’s one more thing you can do: clean up your blade with a cork. Simply draw the bevel through the cork, and it will remove any last traces of burr.
Testing Your Work
Let The Results Show
There are many different ways — both objective and subjective — to check for a knife’s sharpness, but only real-world use will allow you to gauge whether the blade is up to your standards. We typically like using firmer fruits and vegetables, though many enthusiasts enjoy the paper test too. Simply angle your knife down and attempt to cut a piece of thinner grade paper, like from a magazine. Assuming that you’ve succeeded in your efforts to sharpen the blade, it should slice right through with no resistance or tears.
How to Sharpen Your Knife
Not convinced that whetstones are the way to go? Never fret, we cover other, less-involved methods in our primer on how to sharpen your knife.