man sharpening lawn mower blade

While we often think of lawns as something extra that’s just there for aesthetic purposes, they actually serve greater functions as long as you properly care for them. Making sure to water your grass enough and sharpen lawn mower blade regularly will help you gain and maintain an amazing lawn so that you can access these benefits.

Some of my fondest memories as a kid are running barefoot across my parents’ lush lawn. Grass provides a soft surface for recreational activities and can even reduce air and noise pollution in suburban areas since it serves as a natural filter. As long as you care for it properly, grass can increase property value up to 20 percent.

Why Sharpen Your Lawnmower Blade?

In order to have a full, healthy lawn, you’ll need to stay on top of remembering to sharpen lawn mower blade. Here are a few reasons why this is so important.

1. Faster Recovery Time

a pile of newly cut grass

When you allow your blade to get dull, it pulls and rips at the grass, leaving tears that may promote fungal growth and weaken the plant. Using a sharp blade, however, will provide a clean cut, letting the grass recover and heal fast.

2. Machine Maintenance

men checking the blade of a lawn mower

Remembering to sharpen lawn mower blade regularly puts less stress on your mower. Lawnmowers aren’t the cheapest of machines out there. So it makes sense to try to preserve the motor on yours by making its job easier with sharp enough blades.

3. Less Stress for You

a lawn mower in a yard

When you keep your lawnmower blades sharp and ready to go, mowing your lawn will become less of a tiresome chore. With sharp blades, you can easily maintain your grass in a short amount of time and end up with a lawn that makes you proud.

How Often Do You Need To Sharpen?

When spring first starts, check your mower blades to ensure they’re ready for the season ahead. But how often should you sharpen them after that? The easy answer to this question is that you should sharpen your blades whenever they’re dull. Otherwise, you can do so two times every season (from May to late October).

Keep in mind that this is a general rule of thumb and may differ depending on the type and size lawn you have. Rougher grasses will require more frequent sharpening, as will larger lawns. Following other general lawn care maintenance tips, and with regular mowing, your grass will look beautiful.

Benefits Of Mowing Your Lawn

Mowing your lawn comes with a few major benefits. First is the aesthetic appeal, of which you can see results right away. Who doesn’t love looking at a freshly mowed lawn? If cared for in the correct way, your lawn can become a serious source of pride for you. While the other benefits of mowing your lawn regularly aren’t as immediately gratifying, they matter just as much (or more):

​Clearing Debris

lawn mower mowing the lawn

Mowing your lawn regularly will keep it healthy and get rid of common grass pests. It can also clear away debris, making sure the grass doesn’t accumulate junk.

​Stronger Grass

man mowing the lawn with a push lawn mower

​The next benefit involves reinforcing the strength of your lawn. When you cut the grass, the healthiest and hardiest blades will do best. Each time you cut the grass, you’re allowing the best shoots the opportunity to grow and take over weaker shoots, leading to a better lawn overall.

​Even Distribution

a newly mown yard

​When you slice your lawn down to a uniform, short level on a regular basis, the growth will get more equal amounts of water, sun, and fertilizer. When you mow consistently in this way, it pays off in the appearance and health of your lawn.

​Extra Fertilizer

sprinkler in a grass field

​Another benefit to remembering to sharpen lawn mower blade and use it regularly is that the grass shavings left behind can help fertilize your grass. Even when you use a bag, some debris will still make it onto the lawn, composting, and revitalizing the soil.

How To Sharpen Your Mower Blade

a dirty lawn mower blades

Whenever you’re planning to work on the blade, you should remove the spark plug. If you don’t, you might accidentally force the piston into the power stroke if the piston is on top of the compression stroke, which could be dangerous. Once you’ve removed the spark plug, follow these steps:

1. Find the Air Filter and Carburetor

Now you’ll want to find the air filter and carburetor. You shouldn’t have trouble spotting the carburetor because it will have cables running to it. Try to keep this side up when you’re tipping your mower to access the blade so that you won’t have to deal with leaking oil next time. You may also want to keep a rag on hand to clean up potential spills from the gas cap on your mower. As soon as you’ve taken the blade off, put the mower right side up until you put the blade back on.

2. Loosen the Bolt

There will typically be a single nut or bolt holding your lawnmower blade on. Keep in mind that you may need to clamp down on the mower blade to get it loose, as it’s typically very tight. You can use a long-handled wrench or breaker bar to loosen the bolt. Using one of these tools will ensure you have enough leverage to loosen stubborn bolts and that your knuckles are a safe distance away from the blade. If the bolt is really rusted or stuck, use penetrating oil to help get it loose.

​3. Mark the New Blade

When you sharpen  lawn mower blade, mark it with paint before taking it out so you can keep track of the right way to reinstall it. People make the mistake of putting them back in upside down more often than you’d guess.

Using A File To Sharpen Lawn Mower Blade

different sizes of file to sharpen lawnmower blade

If you want to use a file to sharpen the blade, clamp it in a vise and use a mill bastard file. File it until the blade is as sharp as a butter knife. As soon as you remove the mower blade, look at it to decide whether you should replace or sharpen it. Using a hand file is better if you’re less experienced with sharpening blades.

Since mower blades use fairly soft steel in their construction, a clean, sharp file should get it sharp enough within 50 strokes or so. In order to get the best edge, make sure you sharpen from the cutting edge’s top side. The file will only cut in one direction, and that’s on the push stroke. If you don’t feel it clamp onto the blade, the file is too dull, or you aren’t pressing hard enough.

Using An Angle Grinder To Sharpen Your Blade

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If you want a quicker way to sharpen your blade or after you have more experience with sharpening blades, you can use an angle grinder to get the job done. Using an angle grinder is easy, fast, and they don’t cost very much. You’ll need a wrench or socket that fits the nut on the blade, and you should use a penetrating lubricant for stubborn nuts. You will also need a wood block, two clamps, and your angle grinder.

First, disconnect the spark plug wire, then tip the mower with the carburetor facing up. Put a sandwich bag under the gas cap, so gas doesn’t leak out the vent when you tip your mower over. Next, clamp a wood block (a 2 by 4 is a good size for this) to the mower side, so the blade stays in place as you loosen it. Use paint to mark the blade, so you reinstall it with the right side up.

Use a breaker bar or socket wrench to loosen the nut. Clamp the blade to your workbench. Put on a face shield, long sleeves, hearing protection, and gloves to follow proper angle grinding safety. Before you begin grinding, try to angle the grinding disc with the blade angle by tipping it up or down and maintain it while you grind. Make sure to keep your grinder moving and don’t use too much pressure, so the blade doesn’t get too hot.

How To Check Blade Balance

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Checking your blade balance is essential for a job well done. To do this, hang your blade on a nail. If one or the other side of the blade dips down, file more off of that side until it doesn’t. Before reinstalling the blade, always check the balance in this way. Using an unbalanced blade can cause vibrations and potentially ruin the bearings or blade shaft.

Alternatively, you can use a blade balancer to check balance after you sharpen lawnmower blade. A balancer is a cone-shaped tool that provides accurate balancing to reduce vibrations, provides a smoother cut, and extends your lawnmower’s life.

You can use this by placing the tool on a level table, then setting the blade onto it. As soon as you get it into place, the blade will either stay balanced or fall to one side. This visual display helps you identify which side needs more grinding.

General Tips For Sharpening Blades

tools for sharpening

Image CC0 Free-photos via Pixabay

When you sharpen lawn mower blade, there are a few general safety and efficiency tips to keep in mind. Observe the rules below to make sure your chore goes as smoothly and hassle-free as possible:

  • ​Tighten the bolt enough

When you reinstall the blade, make sure you tighten the bolt enough. While over-tightening is difficult and doesn’t happen often; under-tightening is common. If the blade is too loose, it can make your mower hard to start and also throw off engine timing. Having a loose blade is a hassle for you and possibly even dangerous, in some cases.

  • ​Sharpening mulching blades

​Mulching blades will need slightly different guidelines than the ones you follow to sharpen lawn mower blade. Mulching blades might have curved or longer cutting edges that require multiple types of files. In some cases, you might have to take it into a blade sharpening service or hardware store. Compared with what you do when you sharpen lawnmower blade, this task is a bit more involved.

  • ​Don’t sharpen too much

​Overheating the metal when you sharpen lawnmower blade will cause it to turn black or blue and brittle. Too sharp of a blade won’t hold an edge properly. When you sharpen, you should only be trying to remove dents and nicks, not trying to get as sharp of an edge as possible. It’s best to make several passes with the grinder along your blade and check your sharpening progress regularly.

tilted lawn mower

Image CCO Titosoft via Pixabay

  • ​Smoothing out gouges or nicks

​Are there different rules for sharpening a beat-up lawnmower blade? If you’re dealing with a very nicked or gouged blade, start off holding your grinder at a right angle in relation to the blade. Then grind the blade edge flat to get rid of the nicks, using light pressure and moving fast. Remember that it’s easy to burn the edge when it’s so thin. Use the correct blade angle again once the nicks are gone. And always remember to make sure the blade on the grinder itself is sharp enough, too.

  • ​Know when to replace your blade

​While it’s understandable to want to try to save money, you should be realistic about when it’s time to invest in a new lawnmower blade. If the blade you’re using is worn thin, bent, cracked, or has deep gouges, it’s better to buy a new one than sharpen it. Visit a lawn equipment store or shop online. Don’t forget to bring your old blade with you so you can get the right match for your mower.

  • ​Make it a habit

​In order to stick with remembering to sharpen lawn mower blade on a regular basis, use a special set of tools for the job. Hang your sharpening tools nearby so you can use them any time. You’d do well to keep another sharp blade on hand, as well, and use it when you need.

Ready To Keep A Beautiful Lawn Year-Round?

a well maintained lawn

Image CC0 Clayton800 via Pixabay

As soon as you sharpen lawn mower blade for the first time, you’ll see that it’s super simple. It will get easier as you do it more and you get more familiar with the muscle memory involved in the task. Once you’ve got it down, it shouldn’t take you more than 10 minutes to sharpen lawn mower blade. Remember to do this at least twice each mowing season.

Last update on 2023-03-27 at 02:46 / Affiliate links / Images from Amazon Product Advertising API


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