Stuart Price
Last Updated

If you want to get smooth grass, then sharpening lawn mower blades is very important. Smooth grass gives your lawn a beautiful look. Dull blades cut the grass roughly. It gives you an unpleasant look and leaves behind a rough lawn. The roughness of grass also affects your lawn greatly.

But on the other hand, sharp blades help you to cut the grass cleanly and in a quick way. Sharp blades will let you maintain and reduce the mowing time of the lawn. When grass is trimmed properly, then the lawn looks beautiful.


When It Becomes Necessary to Sharpen a Lawn Mower Blade?

If you want a healthy and beautiful lawn, then you have to sharpen the lawnmower blade. When it becomes necessary to sharpen the lawnmower blade, it is an important question for many people.

Many people do not know when they should sharpen a lawnmower blade. Well, some signs can help you to know when sharpening the lawnmower blade becomes necessary. When you are mowing the grass, then have an eye on these signs;

  • The tips of the grass get brown.
  • During mowing, the blades of grass look torn. It does not look like they are finely cut.
  • You see rough grass and an uneven look of the lawn.
  • The blades of grass have some dents or nicks.

When you see any of these signs, then you should sharpen your lawnmower blade. After every mow, try to make your habit of checking the condition of the blade. It will save you from any unpleasant surprises. You can also keep an extra blade to sharpen and replace it at the required time.


Tool Required to Sharpen lawn Mower Blade

Some tools are necessary to sharpen the lawnmower blade. These necessary tools include;

  • Rags
  • A vice
  • A wrench
  • Safety glasses
  • Blade balancer
  • Safety gloves
  • Scraper

These are some important tools that are necessary to sharpen lawnmower blades.


Steps to Sharpen Lawn Mower Blades

There are some different ways by which you can sharpen your lawnmower blades. You can sharpen the blades with an angle grinder, hand file, rotary tool, or with the help of a bench grinder.

You can utilize it any way that suits you best. The most simple and quick method is sharpening the lawnmower blades by using a sharpening stone. This drill and sharpening stone is specially designed to sharpen the lawnmower blades.

Step 1: Remove Spark Plug

To sharpen the blade; firstly, it is important to remove the spark plug. If the ignition wire remains connected with the spark plug, then the engine might start up accidentally.

Disconnecting the spark plug and ignition wire will eliminate the chance of starting up the engine when you sharpen the mower. When you remove blades, also remove the pipe of the gas tank. By doing this, the fuel cannot spill.

Step 2: Remove Retaining Nut

The retaining nut helps to secure the blade on the lower side of the lawnmower. You have to remove the retaining nut or bolt. For this, use a ratcheting wrench and socket. It will make you lose the nut. When it gets loose, you can easily remove the nut.

When the retaining nut or bolt is removed, then it becomes easier to pull off the blade. Remove the blade and also keep in mind which side of the blade faces in a downward direction. It will help you when you have to bolt the blade again.

Step 3: Clean the Underside of Mowing Deck

After removing the blade, there is a need to clean the underside of the mowing deck. Take a narrow-blade knife to clean its underside. The knife will make you remove all grass, mud, and leaves that stick on the underside of the deck.

After cleaning the deck, clean the sides of the lawnmower blade. For this, you have to spray the penetrating oil, and then you have to scrub it with a stiff brush.

Step 4: Clamp Blade at Right Angle

There is a cutting edge on the lawnmower blade. The length of these cutting-edge is about 3 or 4 inches. Handle the blade at an angle so that the cutting edge of the blade is facing up.

It will help you to sharpen the lawnmower blade easily. The cutting edges are also present on the opposite sides, so you have to sharpen both sides.


Step 5: Use Tools to Sharpen the Blade

There are different tools by which you can easily sharpen the lawnmower blades. These different tools include

  • Sharp Lawn Mower Blade with File

An easy way to sharpen the dull lawnmower blade is a flat file. Handle the blade properly and start applying pressure to the file. Further, run the file in the perpendicular direction along with the edge of the blade.

It will help you grind down the metal and hone according to the sharpness of the existing edge. Apply pressure on the file and do this process many times.

Once you have the desired sharpening, repeat the same process on the other side of the lawnmower blade. This process is a little bit slower, but it works completely.

  • Use Drill stone for Blade Sharpener

Another way that you can use to sharpen a lawnmower blade is by using a drill blade sharpener. This sharpener consists of a round-shaped stone. It has a steel shank that is about 1/4 inches in diameter. It also has a flat sharpening guide.

The surface of the stone helps to grind the exact cutting angle of the blade. For sharpening, firstly, you have to put on safety glasses. Be careful about all safety measures.

Attach the sharpening stone with a drill. Now press the trigger, and the drill starts running at its full speed. After that, start spinning the edge of the blades along with the sharpener.

The blade’s flat surface should be on your side, and the dull cutting edges should face the stone. Now move the stone back and forth by a suitable pressure.

After five to six strokes, check the sharpness of the blade. Repeat the process until you get the desired sharpness of the blade; after sharpening one side, now sharpen its opposite side.

  • Sharp with a Bench Grinder

You can also use the bench grinder for the sharpening of the blades. It is the fastest way to sharpen the lawnmower blade. For doing this, firstly, you have to take care of all safety measures.

Wear protective eyeglasses, work gloves, and earplugs. After keeping all the safety measures considered, now grind the spinning wheel and the blade’s edges.

When the blade’s edges and spinning wheel grind with each other, you will see sparks. By this, you can sharpen the blade in just a few minutes. Grind both the sides of the lawnmower blade on the spinning wheel to get correct sharpness.

Step 6: Balance the Blade

After sharpening the cutting edges, the next very important step is balancing the blade. When you are sharpening your lawnmower blade then sometimes it can cause unbalancing of the blade.

Unbalancing the blade means removing more metal from one side of the blade than from the other side. If you use an unbalanced blade, then it can cause wobbling.

Wobbling will put a large amount of stress on the mower, due to which you cannot get the desired result. Also, wobbling can damage the motor. There are some ways by which you can determine whether the blade is balanced or not.

  • Nail in the Wall Technique

For this, there is a hole present in the center of the blade. Slip this center hole of the blade on the nail protruding from the wall in a horizontal position.

If the blade rotates and moves in the vertical position, the blade is not balanced at all. For this, you have to sharpen the heavy end of the blade. Sharpening, then remove some metal from this side and reset it.

  • Lawn Mower Blade Balancer

If you want more precise results to balance the blade, then a lawnmower blade balancer will assist you in this matter. The lawnmower blade balancer is a cone-shaped metal that is multi-tiered.

For balancing, firstly, place the lawnmower blade balancer on a flat surface so that you can get a precise result. After this, set the blade on the top of the balance. The lawnmower blade balancer accepts the blade with center holes of different diameters.

If the blade is balanced, then the lawnmower blade balancer remains in level. If the blade is not balanced, it will move on the side from where the blade is heavier. It will show you where there is a need to do the extra sharpening.

Step 7: Place the Blade Back in Mower

Besides, after sharpening and balancing the blade, the last step is to place it back in the mower. Place the blade in the mower in its right place. After placing it, use the wrench and tighten the retaining nut or bolt.

Further, tighten the bolt carefully. Now attach the ignition wire. Fill the gas tank, and your lawnmower blade is again ready to give you desired results.


How to Perform Better Maintenance of A Lawn Mower?

With time, it is important to maintain the lawnmower. If your lawnmower is maintained, then it can cut easily and cleanly. For maintaining it, you have to keep some points in mind. These points include;

  • Use Clean and Fresh Gas: For maintaining the lawnmower, it is vital to make sure that you use clean and fresh gas. For this purpose, you can use a fuel enhancer or make it possible not to use ethanol at all. Ethanol lowers the efficiency of your lawnmower blade.
  • Spark Plug Wire: If there is a need, then loosen the spark plug wire. Or, if there is a need to clean the wire, then unscrew the spark plug and clean it. After cleaning, keep it in place or replace it with a new wire if needed. Cleaning spark plug wire helps you in better maintenance of the lawnmower.
  • Clean Air Filter: There is always a need to clean the air filter. If your air filter does not work properly, you have to replace it according to your need. If your lawnmower does not start easily or it takes many pulls on the rope to start, then you have to examine the issue. If even examining the issue does not work for you, then you have to check it professionally. You can also take it to the shop. Always make sure that you check your lawnmower earlier rather than taking a risk at the last minute. If you check it frequently, then it will save you from spending money on maintenance.


Why is Sharpening Lawn Mower Blades Important?

Many people think that sharpening the lawnmower blades is not that important. If you want a high-quality cut, then sharpening the lawnmower blades is quite essential. There are some disadvantages of a dull lawnmower blade that help you understand the importance of a sharp blade.


Advantages of a Sharp Lawn Mower Blade

On the other hand, if you sharpen your lawnmower blade, then you can see many advantages. The sharp blade cut the grass cleanly. When the grass is cut cleanly, it will allow the grass to recover and heal quickly. A sharp blade also reduces the mowing time. In a small amount of time, you can cut the grass on your lawn.


Disadvantages of a Dull Lawn Mower Blade

Lawn Mower blades that get dull have many disadvantages. A dull blade rips the grass; it pulls the grass by leaving behind ragged tips. It then weakens the plant badly.

This unusual cutting of grass also promotes the growth of fungus and causes diseases of grass. If you are facing such a problem on your lawn, then sharpen your lawnmower blades.



If you do not know how to sharpen lawn mower blades, then this article is for you. Here, you will learn a few simple steps to sharpen the lawnmower blades. You will also find the advantages of shape blades.


Social Share