With continued use, the edges of your Japanese kitchen knives will inevitably become dull. When edges lose their sharpness they hinder a knives’ effectiveness for making clean cuts when preparing food. With proper maintenance your knives will stay in great condition and can last a lifetime. Here we’ll walk you through the steps on how to sharpen a knife correctly.
Understanding Sharpening Stones
To understand how to sharpen a knife correctly, you’ll need to know about sharpening stones, which are the most important tool for sharpening knives. Stones come in three main categories: rough, medium, and fine. These distinctions are based on their surface texture are are rated by grit #, with lowest being the roughest and highest being the finest. Rough stones (#200 to #800) are necessary for repairing damage like chips and tip issues. They remove a lot of material and should be used with caution.
Medium stones (#800 to #1500) are for general maintenance sharpening. They are necessary to take a small amount of metal off the blade, since that is what creates a new sharp cutting surface. Lastly, fine stones (#2000 to #8000) create a razor sharp polish that helps you cut with extreme precision. You will usually need more than one stone from start to finish and should always start with the roughest necessary and move your way up to fine or polishing stones.
Now we move on to the actual sharpening, which is an essential kitchen skill for maintaining your Japanese kitchen knives. Here, we’ll go over the basic process using medium and fine stones.
- Before you start, soak your stones for about 10 minutes. After this, place a damp cloth or stone base underneath them to prevent them from slipping.
- Set up your medium grit stone and hold your knife with your index finger on its spine and thumb on top of its blade face with the reverse side facing down on the stone. With the other hand, press down on the blade end near the tip so the blade is flat on the stone.
- Begin sliding the knife’s reverse side back and forth on the stone, moving its entire length from tip to base over the stone. This will prevent the reverse side from becoming brittle, which happens when you only pay attention to one side of the knife.
- Once you see a sharpening sludge called ‘slurry’ appear (the metallic particles mixed in with water on the stone), flip the knife over to its primary side. Again, you should move it back and forth as you slide slowly down from blade tip to base. Hold a couple of your fingers over the part of the edge you’re focusing on at every moment to ensure the knife receives enough pressure.
- Run your fingers lightly over the reverse side of the blade. You should feel a slight bump at the edge. This is called a burr; it results from the metal slightly curling away as you sharpen the primary side. You’ll need to smooth out the reverse side and remove the burr by flipping the knife back to its reverse side and running it over the stone as before.
Switch to the fine stone and repeat this process, starting with the knife’s reverse side. When you sharpen the primary side, focus on pressing closer to the blade edge. As you proceed, exert less and less pressure. After this, your Japanese cutting knife will be as good as new.