Sharpening a Knife Correctly

There is a simple rule: it's easier to cut yourself with a blunt knife than with a sharp knife. That is because with a blunt knife, you need to apply more force in order to cut or slice something, and then the knife slips easily and causes injuries. This is why you should regularly sharpen your hunting knives or kitchen knives.  

How to Sharpen Your Knife at Home

Avoid simple hand-held sharpeners. They make the blade heat up, tampering with the material structure, resulting in lower durability. Another disadvantage of hand-held sharpeners is that they only sharpen the blade at single angle. But different types of knives require sharpening at different angles (anything between 15-45°). These simple sharpeners are, however, fully sufficient when you are traveling. 

So how should you sharpen your knives?

Whetstone

An ideal way of sharpening is applying oil or water to a whetstone. Whetstones are made of special materials, such as carborundum or heat-treated silicon carbide. Whetstones or sharpening stones come in many shapes (round, oval, triangular or square).

How to choose the right whetstone?

When choosing a sharpening stone, make sure to choose the right grit:

• Japanese knives use JIF,
• and European standard uses FEPA F.

For rough sharpening, you need stones with 100-600 grit.This sharpener will remove chips along the edge and restore the original angle and shape of the blade.

For fine to very fine sharpening, you need 600-1200 grit.That will restore sharpness.

You can also use an extra fine, finishing stone with 2000-8000 grit to polish the blade.         

Step-by-step instructions for using a sharpening stone

Before you start, soak the whetstone in water for around 5 minutes. Water will act as lubrication, help the sharpening process and protect the blade from damage. Always follow the instructions you received for the given stone. 

The key to sharpening a knife on a whetstone is a correct and consistent angle. The angle varies for different types of knives.

• Standard kitchen knives require the angle of 15°,
• While Japanese and filleting knives require the angle of 15-20°,
• and hunting knives require 25–28°.

The picture below shows the edge of a new, industrially produced knife. To protect the edge from breaking off, you need to change the angle towards the end of the edge.

If you cannot keep constant angle throughout the grinding process, you can get a simple sharpening guide clip. It has two ceramic gliders on either side to glide on the whetstone without damaging it.

 The instructions below are valid for right-handed people. Left-handed people need to do everything to the opposite side.

1. Place the blade at the correct angle to the heel of the grinding stone (the end which is further away from you) and draw the knife down and across the stone, finishing at the tip. Hold the knife handle with one hand, while resting the fingers of the other hand on the flat side of the blade.

Do not push the knife down too hard, or you can damage the blade. The stone should remain wet for the whole sharpening process.

2. Draw the knife across the stone at constant speed and constant angle.

3. At the end of the motion, the tip of the blade should be towards the right side of the tip of whetstone. Make sure not to draw the blade over the edge of the stone, so as not to damage the knife or the stone. Make the same motion with the knife as if you wanted to cut a thin layer off the surface of the stone.

4. Repeat the motion several times and check the sharpness. Don’t forget to flip the knife each time to sharpen the other side of the blade equally. As soon as you see a burr (a bit of waste metal forming at the edge), sharpen the other side of the blade. We recommend the count the number of times you draw the blade across the stone on one side and keep the same number of times for the other side.

From time to time, you can flip the stone as well. 

Still not sure how to sharpen your knife? Check our video guide:

Sharpening Steel

Remember, you cannot use sharpening steel to sharpen blunt knives. The purpose of sharpening steel is to re-align blade edges, to maintain and lengthen the time the knife stays sharp, not to sharpen a blunt knife. 

If you want to learn how to use sharpening steel, you can use a cheap knife for training. You need to coordinate the motion of two objects, the sharpening (honing) steel and the knife. 

Step-by-step instructions for using a sharpening steel:

1. Brace the end of the steel rod up against the table. If the table is slippery, put the tip upwards and the handle down against the table, hold the handle with your hand and keep it in position on the table.

2. Take a knife into your other hand. Place the knife at the handle to the upper part of the steel rod and draw it towards the end, finishing at the tip of the knife. The motion must be smooth, accurate and at constant angle. If you see microscopic teeth broken away from the blade, the angle needs to be smaller.

3. Repeat the motion a few times. Again, keep the same number of motions for both sides of the blade. Don't forget to be extremely careful. 

If you need more details about how to use a honing steel, check out the video
Knife Sharpening : Knife Sharpening Techniques for Steel 

When should you take your knife to a professional?

Is your knife extremely dull, or with teeth broken away from the blade? Don't try to sharpen it at home and take it to a professional. 

How do you know if a knife is extremely blunt?

The left picture shows a well-maintained blade - you can easily sharpen such knives at home. The blade in the right picture is extremely dull, and it is better to have it sharpened by a professional.

Do you want to buy a new set of kitchen knives, but you don’t know what to choose? Check out our article about different types of knives.