How To Sharpen A Blade (7 Methods You Can Use)

how to sharpen a blade

Does it bother you as well to work with a dull knife? For me, it is very frustrating. It takes extra effort, and sometimes you make a big mess with the food. Especially if you have to cut tomatoes and onion.

Luckily for us, there are many different methods that you can use to sharpen a knife. In this article, I am going to reveal seven ways that you can use to sharpen a knife at home. You do not always need to seek the help of a knife maker to do it for you.

I am also going to reveal the difference between sharpening and honing. You will also learn how to test for sharpness and how to look after your knives.

Are you ready to learn?

Sharpening Vs. Honing

Some people get confused and do not know the difference between sharpening and honing a knife’s edge. Both of these methods will make your knife cut more efficiently, but they have a different effect on the edge of the blade.

Sharpening

dull vs sharp edge

When you sharpen a blade, it means the edge is dull. Steel is a type of metal that can get worn out after several uses. Especially if you cut hard materials such as bones and wood, the edge will get blunt. 

It will not be visible through the naked eye, but if you look it through a microscope, you will see the difference. By sharpening the blade, you will shave off some of the steel on the edge of the blade to create a new sharp edge.

Most of the methods shown in this article will help you to sharpen a blade. You also do not need to grind a blade every time as you will waste the metal which will reduce the lifetime of the knife. 

Honing (Steeling)

honing a knife

It can also be called “steeling.” After several uses, the sharp edge of the blade will start to bend. The closer you move to the tip of the edge, the thinner it becomes. 

It is usually in this area where the edge will bend slightly. When it bends, it will not be as sharp as a knife with a straight edge. You will notice that most professional chefs will hone the blade with a honing rod instead of sharpening it.

Gordon Ramsay is very famous for honing all of his knives before it is used. It is also his signature move.You will also notice that the tip of the edge will have a wavy appearance when looked under a microscope. Not a lot of pressure is needed for the tip of the edge to bend.

The process of steeling or honing will realign the tip of the edge to the center of the blade. Once this process is done, the blade will be sharp again. This process needs to be done more frequently than sharpening. 

7 Methods To Sharpen A Blade

In this section, I am going to discuss some of the methods that you can use to sharpen a blade. I am going to discuss seven ways and let’s start with the whetstone.

Method 1. Using A Whetstone

Whetstones are the most commonly used, and it also gives you the most freedom regarding angles. The only drawback is that it needs a skilled individual to consistently hold the same angle.

Step 1. Choosing the stone

whetstone

There are many different types of whetstones that you can buy. What makes most of them different are the texture of the stone. Some will be very coarse and can range from 200 to 1500 grit.

You will also have finer stones which can reach up to 8000 grit. The courser the grit, the more metal it will shave off the knife. A finer grit will shave less metal from the edge of the knife but will make it sharper.

Here is a rule of thumb:

  • For damaged blades. If the edge of your knife is damaged, then you need to use stone with a texture of less than 1000 grit. It will remove the most metal and will create a new edge. This helps when the edge is worn out or if there is a chip in the edge.
  • For a very dull knife. For a knife that still has its edge, but is very dull, you will need to use a stone that has between 1000 and 2000 grit. This texture will restore the cutting edge without shaving off too many metal from the edge.
  • To make a knife sharp. Now that your edge has a nice form, you can not start to sharpen it. To do this, you need a texture of between 2000 to 4000 grit to sharpen the blade. It will not shave a lot of metal from the edge.
  • Take sharpness to the next level. If you want a knife that can shave the hair from your arms, then you need to use a stone that has between 4000 to 8000 grit. The higher the grit the sharper the knife. This stone will be super fine and will sharpen the edge of the blade on a microscopic level.

Step 2. Lubricating the stone

lubricating whetstones

Make sure that when buying a whetstone that you know what type it is. Some types need to be submerged under water or need to be covered with oil instead of water. You will also find stones that do not need any moisture at all.When submerged underwater, the water will fill the pores and will prevent the stone from drying out. You want to soak the stones for as long as the bubbles stop coming out of the stone.

The oil will catch some of the swarf that comes from the knife so that it does not clog the pores of the stone. It also makes it easier to remove the swarf on the surface of the stone to give you an edge that is straight and even.

Regularly wipe the stone clean and reapply the oil and water. Oil and water also reduce the heat between the knife and the stone.

Step 3. Securing The Correct Angle

Before sharpening a blade, you want to make sure that you do it at the same angle as the edge of the blade. Otherwise, you will shave off too many steel from the edge of the blade which is a waste.

It will also take longer and more effort from your part to reproduce the new edge. This mistake is especially true if you use a finer-grained whetstone.One tip that I would recommend is using a black permanent marker. Mark the edge with the black marker to identify it.

Move the edge over a whetstone a couple of time at an angle. Take a second look at the edge to monitor its effect on the black marks on the edge. If the black area produced by the marker is completely shaved off, then you have found the correct angle to use. If only the area close to the tip is shaved, then you need to lower the angle. If only the area closer to the beginning of the edge is shaved, then you will need to increase the angle.

Most professional knife sharpeners need to look at the edge with a magnifying glass to find the correct angle.

Step 4. Sharpening The Knife

If your knife is very dull, then I would recommend you to start on the coarse side first. When sharpening knives, you always start from the side that is the rudest and then move to the finer side.

Place the blade at the predetermined angle. Most knives will have an edge that has a 10 to 20-degree angle.

  • Hand placement. Place your hand on the middle of the flat side of the blade away from the sharp edge. The direction of the movement should be away from your body. Watch the video above for a visual presentation.
  • Use a circular movement. Move the knife forward in the direction of the sharp where it will represent a sweeping arc motion. In a slicing motion, bring the heel of the knife through the stone until it reaches the tip of the blade. 
  • Do not apply too much pressure. You do not want to put too much pressure on the knife. Make sure to apply the same amount of pressure throughout the whole process. The tip of the knife should also not slip over the edge of the stone as it can cause irregularities on that part of the blade.
  • Only 10 strokes on each side. There are no set rules as to the number of strokes per side, but I usually do ten strokes per side. After the first stroke move the knife backward until it reaches the starting point of the stone while still applying some pressure. Repeat it ten times and move to the other side.

There is no set amount of rounds that you should stick to. I like to do it for only eight rounds (eight rounds times ten strokes is 80 strokes per side).

After you are finished with the rough area of the stone, turn it over and do the same on the finer side. Do not forget to wipe the dirty oil off the stone and replacing it with clean oil. You will notice that the oil will become darker in color which is a sign that your knife is getting sharper.

Another thing to remember is to always stick to the same angle and amount of pressure. You can place a coin under the blunt side of the knife. Some stones will also come with detachable arms that will be of great help in sticking to the same angle.

After you are finished, you can always test the sharpness of the blade by the methods that I will describe at the end.

Method 2. Honing Rod (Sharpening Steel)

Honing rods are not used for sharpening a knife but honing the edge of the blade. It can also be called a steel rod. The honing rod will shave very little steel from the blade which makes it ideal for frequent use.

The point of the edge that comes into contact with the object that you want to cut will frequently bend. It will cause the knife to lose its sharp edge.

Instead of carving away some of the steel, this tool will only realign it to the center making it sharp again. It is also best to use a honing rod in between cutting sessions. The reason why this tool works is that it is much harder than your knife.

Here is how to use it:

  • Holding positions. You will hold the knife in your dominant hand while you hold the rod in your non-dominant hand. You want to keep the rod in front of you at a 90-degree angle. The knife should be placed on the rod with the edge facing away from you.
  • Pulling the blade over. You want to hold the knife at a 15-degree angle or similar to that of the edge. Make sure that only the edge is touching the rod. Pull the edge of the blade over the rod with little force.
  • Switching sides. Only run the knife along the rod once. Place the edge of the blade against the opposite side of the rod and repeat. Do this for at least 20 times per side resulting in a total of 40 times.

Another method is to hold vertically while the rip of the rod is anchored on a wooden board. Place the knife against the rod at a 45-degree angle with the sharp part facing away from you.

While moving it down the rod, you will also pull it inwards so that you cover the entire length of the edge. Take a look at the video above for a full demonstration.

Method 3. Triangle Sharpener

triangle sharpener

This is one of the easiest methods so far. As long as you can eyeball a 90-degree angle, you will be able to use it. This tool can also be called the stick sharpener. The material for the rod will mostly be made out of ceramic.This tool makes use of two sets of ground rods. The first set will have a coarse texture while the second set will be fine. These rods will then be inserted into the holes of a flat and small platform.

Use it this way:

  • Install the grinding rods. The holes will be made at different angles so that once you insert the rod, it will also be at an angle. Some of the angles will include from a 15 up to a 30-degree angle. Start with the rods that have a coarse texture. Once the rods are set, you will need to place the other two safety rods.
  • Position the knife. Place the knife at a 90-degree angle where the blade must be perfectly vertical. Place it at an angle as if you would cut a watermelon in a downwards motion from above.
  • Push it down. Now that your knife is in the position, you can start to pull it down and also towards you until it touches the platform. Start with the rod on the left and then move on to the rod to the right.
  • Switch to the fine rods. Once you are finished with the coarse rods, you can now move onto the finer ones to add some extra sharpness to your blade. Swipe the knife down the rods for at least 25 times per side.

Method 4. Bench Grinder

bench grinder method

You will see a lot of blacksmiths that will use a bench grinder to create the initial edge of the knife. Once this method has produced the edge, they will move to a more subtle approach such as a whetstone to finish it off.

I tried this method once and made a huge mistake. Instead of using a grinding wheel of medium coarseness, I used a very coarse wheel. I ended up damaging the edge to the point where I had to throw the knife away. A bench grinder can go far over 1000 rpm’s which is why it should be used sparingly and gently.

I would also go so far as to say that you should not use the regular grinding wheels because they are too aggressive. Instead, get a razor-sharp edge making system which is a bench grinder wheel specifically made for sharpening knives.

The wheels will be made out of paper or wood with an abrasive on it. You will also need to add some wax to the abrasive for lowering the temperature of the blade.

Put the knife on top of the spinning wheel while the edge is in the same direction as the rotation of the wheel. Put it at the desired angle and run it through 5 times.Do not put much pressure on it and let the wheel do the working. Turn the blade over and give the other side some grinding.

Do this for two to three sessions until you notice the knife is sharp. Have a look at the video above for more information.

Method 5. Belt Grinder

Have you ever wondered how professional knife makers or blacksmiths sharpen their blades? They use a belt grinder. They can, however, use whetstones and triangle sharpeners but it takes too much time.

If you want to get more familiar with belt grinders, then read this review on 5 of the best belt grinders for knife making.

It belt grinder might not be that accurate but is much more productive. If you are a belt grinder, then I would highly recommend this method. It works with the same principle as the bench grinder, but instead of wheels, this one uses sanding belts.

It is more effective because the belts are flexible which will make it less sensitive to applied pressure from the knife giving you a more even finish.You can start with a 220 grit belt. While using this method, you want to apply as little pressure as possible. Let the belt do the work for you.

Place the blade on the belt, so that movement of the belt runs against the edge of the blade.

Run the blade horizontally across the belt up and down with four strokes. Turn the blade around and do the other side as well. You might want to frequently put the blade in cold water to cool it down.

Do this cycle for 5 to 6 times. You should continuously inspect the edge so that you do not overdo it.You can do this until you spot a visible burr. Is burr is the first sign that both sides of the edges have met each other. This is an indicator that you can move on to the next step.

The next step is where you will use a leather belt for knife stropping which will turn the knife dangerously sharp. In the next section, I will discuss stropping with leather in more detail.

Method 6. Stropping

stropping a blade

Stropping is the last step that you will take to sharpen a blade. This method will not remove a lot of steel as you will make use of leather.

As discussed in the previous process, I mentioned burr which is the result of the intersection of the two sides of the edge. This is a sign that the edge is in the final phase and ready to be finished. The leather is used because it is soft enough not to modify the edge of the blade further but hard enough to remove the burr.

You will notice a lot of barbers will use this method to sharpen their straight razors. If your knife has gone through this process, it will be able to shave the hairs on your arm.

Method 7. Using A Coffee Mug

If you do not have access to a knife sharpener and you desperately need to sharpen it, then you can use the bottom side of a coffee mug.

Make sure that the base is not glazed and still have some roughness to it. Place the knife on the rim of the base at a 15 to 20-degree angle and run it through several times.

How To Test For Sharpness

When in the process of sharpening a blade, you want to test its sharpness regularly. This way you will know when to stop so that you do not waste the steel on your knife with grinding. These are several methods to test sharpness.

Cutting A Tomato

It is best to use a very ripe tomato because the skin will be extra tough and the flesh will be very soft. You want to put the edge of the knife on the tomato and cut through it with very little force.

If you apply too much force, the tomato will become squishy which is an indicator of too much force. If it cuts through the skin with ease, then it is very sharp.

Testing On Your Nail

This is my favorite method to test the sharpness without cutting myself. It is best to use the nail of your thumb as it is the thickest. Slightly tap the edge of the knife on the nail with minimal force.

Then you should try to move it up and down on your nail. It will feel like the blade is “biting” your nail. It will give this feeling because it penetrated your nail with a fraction of a millimeter and because your nail is hard.

Using Paper

You can also use paper to test the sharpness. Take one sheet of paper and run the edge of the blade of the side of the paper.

If it manages to cut through the paper, then it is sharp. If the knife is still dull, it will tear into the paper instead of cutting it.

Shave Your Arm Hair

If your knife is sharp enough to shave the hair on your arm or leg, then you have mastered knife sharpening. Use your knife as you would use a straight razor. 

Looking After The Knife Edge

There is a straightforward rule that you must follow. Never cut an object that is as hard as steel or even harder. Steel is a tough material, but all it takes is a simple bump against another hard surface to flatten or bend the edge.

  • Cutting on hard surfaces. Marble and granite is also a tough material which will quickly damage the edge of your knife. You should instead use a plastic or wooden board to cut on. You do not want to cut on steel surfaces as well. It is also advised not to cut through bones.
  • Using the right blade. If you want to process a deer carcass or slice through large and hard items, then you better use a knife that is longer and also thicker. Do not waste your Leatherman knife on for heavy duty work.
  • Cut in a straight movement. If you are moving your knife sideways while cutting, you will bend the edge which will then require you to hone of the blade.
  • Use a knife block. Most people are guilty at throwing their knives in the drawer which might damage the edge. Instead, put your knives inside a knife block which will protect the edge.
  • Clean the knives. You should always clean your blades after peeling that juicy orange. Citrus fruits are acidic and can corrode the edge of your knife.

Now It Is Up To You

As you can see, there are many ways to sharpen a knife. My favorite was the belt grinder as it is the most efficient and does not consume too much of your time. I also like the honing rod which can keep your blade sharp. Which method are you going to try next? Leave a comment below and share with us your plan.

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