How to Sharpen a Knife With a Whetstone

Sharpening a knife with a whetstone
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The best way of sharpening a knife is with a whetstone. There are other methods and devices available for knife sharpening, but most of them tend to grind away too much of your knife's blade.

Learning the right way to use a whetstone may take a bit of practice, but once you get the hang of it, you'll be able to keep knives razor sharp while saving time and money.

As counterintuitive as it sounds, sharp knives are actually safer to use than dull ones.

Dull knives force you to apply more pressure to achieve the cut you want, and pressing down harder can cause the knife to slip. So not only do you cut yourself, but you cut yourself worse because you were applying more force to the knife. 

What You'll Need

To begin, get yourself a two-sided whetstone, with a coarse grit on one side and a fine grit on the other. Different knives require the edge of the knife to be applied to the stone at a different angle, depending on the manufacturing specs. In general, it's somewhere around 22 degrees.

To visualize this, picture 90 degrees, which is straight up and down. Then imagine half of that, which is 45 degrees. And then another half of that is 22 1/2 degrees. Don't worry about the half degree. But do consult the technical info that came with your knife, or check with the manufacturer to verify the correct angle you should be using.

Keep It Dry

While there is such a thing as a water stone, which is designed to work under running water, a whetstone needs to be kept dry.

Don't let the name confuse you. Using oil or water on a whetstone traps tiny metal particles in the liquid, which in turn produce a more ragged edge than when using a dry stone.

How to Sharpen Your Knife With a Whetstone

  1. Place the whetstone on a cutting board or countertop, with the coarse grit face up. Place a wet paper towel underneath the stone can help keep it from sliding.
  1. With one hand, grasp the knife by the handle and hold the edge of the knife against the stone, point-first, with the cutting edge meeting the stone at around a 22-degree angle. You can stabilize the blade with your other hand.
  2. With moderate pressure, slide the blade forward and across the whetstone, covering the entire length of the blade and keeping the blade flush against the stone at a constant 22-degree angle.
  3. Do this ten times, then flip the knife over and give the other side of the blade ten strokes on the whetstone.
  4. Now flip the whetstone over to the fine grit side and give each side of the blade ten strokes.
  5. Finish by using a sharpening steel to hone the blade, then rinse and wipe the blade dry to remove any metal particles.

Tips for Sharpening Knives

  • Always sharpen in the same direction, whether it's front-to-back or back-to-front.
  • Don't believe the hype about knives that supposedly "never need sharpening." Cutting produces friction, and friction causes a knife's edge to lose its sharpness. There's no avoiding the laws of physics.
  • Don't attempt to sharpen ceramic knives; they are brittle and prone to breaking.
  • Remember, it's a whetstone, not a "wet stone."
  • Finally, don't forget about professional knife sharpeners. For your time and money, that might be the most effective way to sharpen your knives, and it's a fairly inexpensive service. Inquire at cutlery stores or even your local butcher shop.