Japanese Knife Sharpening 101

Japanese chef knives are designed with one objective in mind: Unparalleled sharpness. From the steel to the design to the shape of the thin blade, this quality is paramount. The sharpness of a Japanese chef knife allows cooks to control their blade and slice with absolute precision. So how do you maintain your Japanese blade at peak sharpness?

To find out, we dug into Korin’s YouTube channel to watch Korin’s master sharpener Vincent Lau‘s key lessons. Here’s what every Japanese knife owner need to know:

First, you’ll want to invest in a #1000 medium grit stone, #6000 grit finishing stone and a stone fixer, as you’ll see shortly. This double-sided stone is a great option, and here’s a stone fixer we rely on.

To start, soak your stones in water before you start sharpening, as follows:

  • for double-sided stones, soak the medium grit side only for 5-10 minutes
  • for medium grit stones, soak for 20-30 minutes
  • please note: do not soak finishing stones

Now let’s go to the video below and watch Vincent break down the steps to knife sharpening:

Key points to keep in mind

Hand position

Hold your knife like it’s an extension of your arm. Keep a straight line from your elbow  down to the tip of the blade to maintain an even angle. Remember to keep your wrist steady, but you don’t have to grip too hard. Think even pressure.

Proper angle

Whatever the degree of bevel of your knife (50/50, 30/70 or another ratio), you want the bevel to lie flat on the stone, so you’re sharpening it correctly.

Back of the knife

  1. Start with the back of the knife first
  2. Hold the knife by putting your thumb on the spine and index finger on the heel
  3. Work down from the tip of the knife to the heel
  4. Move your fingers to apply even pressure, working in sections
  5. Apply pressure when pulling the knife down the stone
  6. Feel for the burr

Front of the knife

  1. Now hold the knife by placing your index finger on the spine and thumb on the heel
  2. Lift your elbow up and rock the knife so the tip makes contact with the stone
  3. Work down from the tip of the knife to the heel
  4. Move your fingers to apply even pressure, working in sections
  5. Apply pressure when pushing the knife up the stone (opposite from the sharpening the back)
  6. Lower your elbow down when you reach the heel so it makes contact with the stone
  7. Feel for the burr

Finishing stone

  1. Press your knife lightly so you don’t crush the edge
  2. Work in slow, smooth motions
  3. Follow Back of knife/Front of knife method
  4. Test the knife by pinching it to make sure there are no burrs left

How To Tell If Your Knife Is Sharp Enough

Now that you’ve followed the techniques we outline, how do you test if your blade is sharp enough? Vincent explains:

The key takeaway here: Use a piece of paper to test for sharpness, the thinner the better, like a newspaper or magazine page. And remember, a sharp knife won’t crush the ingredients you’re slicing—your food will look more beautiful and taste better!

How To Avoid Common Sharpening Mistakes

In this video, Vincent talks about the three most common mistakes people make sharpening their knives, and how to avoid them:

When you’re sharpening, keep these three points in mind:

  1. Always follow the angle of the bevel
  2. Don’t sharpen with too high an angle
  3. Don’t switch hands as you sharpen

Knife Care Tips

Keeping your knife in top shape involves more than just deft sharpening. How you clean your knife, store it and the cutting board you choose all effect the blade, and its sharpness.

How to Clean Your Knife

What’s the best way to clean your Japanese chef knife? Korin master sharpener Vincent Lau explains:

Remember these tips to clean your knife:

  1. Use warm water, soap and sponge
  2. Keep your blade flat against your work surface as you clean
  3. Always completely dry your knife before you store it
  4. Use a polishing compound to get rid of stubborn dirt
  5. Never place your knife in a dishwasher to clean it, which can ruin the blade

How to Store Your Knife

Storing your knife the wrong way can quickly damage your blade. Keep these points in mind:

  1. Use a wooden Japanese saya knife sheath or a plastic edge guard to protect your blade
  2. Avoid using magnetic strips to store your knife, which can weaken the blade’s metal
  3. Knife blocks are fine, just make sure the block is large enough to protect the entire blade
  4. Never store your knife in a drawer without a sheath or edge guard

Using the Right Cutting Board

Remember one thing when choosing a cutting board: the softer material, the better.

A Japanese Hi-Soft cutting board is ideal.  Produced from a hi-tech Japanese composite, it minimizes the impact of your knife and preserves your blade. It’s pricier than other boards, but with proper care and cleaning, you’ll use it for many years and your knives will last longer, too.

Avoid the following cutting board materials, which can easily crush and damage the edge of your Japanese chef knife:

  • Hard wood
  • Glass
  • Bamboo
  • Granite (including countertops)

Chef's Corner