Archive for December, 2007

How to remove nicks when sharpening

nicked blade

Nicks make your blade look unattractive, but more importantly, they get in the way of cutting. You need to work the nicks out of your blade before you move on to fine sharpening. Concentrate to grind down the damaged area until the nicks are gone. After that, switch to sharpening the blade’s entire length and evening out the blade, either with one sweeping motion, or by using a circular, counter-clockwise motion.

Knife-to-stone contact

You will need to be sure you keep the blade in constant contact with the sharpening stone and that it maintains steady pressure as you go. Pay careful attention to the very tip of the blade as many beginners have a tendency to push too hard at the last moment or to lift the tip off too lightly.

Choose your angle

Sharpening AngleSharpening AngleBy tweaking the angle at which your hold your knife while sharpening it, you can change the angle of the blade to better equip it for the tasks you wish to undertake. Decrease all of your sharpening angles by 5 or 10 degrees to get a fine, silk-like cutting edge. Be aware, though, that this will weaken your blade, making it more prone to damage. Angling your blade in the opposite direction, will produce a blunter, more pyramid-like edge, that’s tough, durable and perfect for chopping.

Different strokes

There is no one right way to actually slide the blade across a sharpening stone. Some go from hilt to tip, others tip to hilt. Some use straight strokes and others more circular ones. If you’re using a small, portable stone, straight strokes are preferred. Keep in mind, though, that you should move the blade’s edge in the direction of your stroke, as if you were trying to take a small sliver out of your sharpening stone. This will create a burr (or a thin ridge) on the blade, but you’ll soon see how to remove those.

How to angle the blade

If you can’t seem to find the perfect angle, you can always cheat. Hunt down the knife’s specs and you’ll know how many degrees away from the edge to aim for. A bowie knife for instance, usually has an angle of about 14 degrees away from the sharpened edge on both sides of the blade. If you know your specs, you can measure your angle with a protractor (if you don’t have one, you can always print out a protractor here: Protracter). Then again, it’s OK if you change the blade’s angle — so long as the change isn’t all that drastic. A blade with a wider angle away from its edge is better suited for chopping. A blade with a tighter angle will be sharper. The key here is to start small using gentle strokes. If you find that you’ve altered the blade’s angle, don’t worry, you can always get it back to the shape you desire.

Scratching your blade

DMT Deluxe Aligner SharpenerUnless you are more experienced, scratching is going to happen when you sharpen your blade. By studying the marks you leave, you can get an idea of how uniform your sharpening strokes are or aren’t. The closer you can keep them to the blade’s original shape and angle’s, the better off you are. If you’re leaving scratches near the back of the blade, you’re holding the blade way too flat against the stone. Over time you’ll get the feel for how to hold and stroke the blade against the stone and you won’t scratch your blade during sharpening. One way to get around this problem is to use an DMT aligner sharpening system. This will guide the blade and keep the angle from changing while you sharpen. DMT has a system like this for under $50. Well worth the money. I have personally tested these angle systems. They are a little slower to use but work well to set the desired angle and produce a razor sharp edge without so much as a single scratch to the blade. Another tip is to roll the knife on the edge to feel where the flat of the edge is. Then you sharpen on that flat edge angle.

Start with a straight blade

Straight knife blades are the most straightforward of all blades, making them the perfect place for beginners to start. Begin by carefully studying the blade in a well-lit space. Hold the knife so the edge points up. Peer down the length of the blade making note of all nicks and flat spots, which will be apparent in the light. The duller the blade, the coarser the stone you’re going to have to start with. Typically, there are three “stages” of sharpening, with Stage 1 referring to the most intensive part of the process. It requires a coarse stone with a grit level of 200 or less. Stages 2 and 3 refer to sharper blades that only need touched up. 2 and three are the final stages of attaining a razor sharp edge.

Advice for new knife sharpeners

Practice on a knife blade you’re not particularly fond of before moving onto your prized possession. It may sound silly, but you’ll be happy if you notice that you’ve scratched your crappy blade and not your best one while you were learning the ends and outs of sharpening. Beginners have a tendency to press too hard or use too severe of an angle when learning to sharpen a knife. They also tend to use less water or oil than an experienced knife sharpener. Throughout the entire process, you should be able to see a small pool of sharpening lubricant on the stone. If the honing oil or water changes color or gets streaky, that means there’s debris trapped in it. Stop sharpening and rinse the stone off. Then, reapply your lubricant and get back to work.

Knife Sharpening Video

Backpacker Magazine published a free video on knife sharpening with some information to absorb. It’s called “Keep Your Knife Sharp” from the Backpacker’s Gear School.

Bad stone equals bad blade

You should treat your sharpener almost as carefully as you treat your blade. If the surface gets damaged that means it’s uneven, which can damage or groove your blade. Always wrap your stone in cloth before storing. If you used oil, make sure there’s still a layer of it coating the stone before you pack it away. If you used a water- or petroleum-based oil, wash your stone with soap and water before stowing it. If you see streaks or filings on your blade, be sure to clean the surface until it’s smooth and spotless. Never use an abrasive brush on your stone. If you must clean it heavily, a soft-bristled toothbrush, or even your finger is enough.