How to Sharpen Your Lawnmower Blades Safely

In gardening, one of the essential equipment you need to have is the lawnmower. It comes in handy when you are leveling your lawn and cuts grass with precision. For your lawnmower to serve you well, you need to have a proper maintenance plan for it. One way to maintain the equipment is by sharpening its blades. Sharpening lawn mower blades ensure that it cuts appropriately, and operating it will be a simple affair. According to the Family Handyman, a blunt edge will weaken the plants and lead to fungal infestations. It also results in rough cuts that will leave your lawn looking untidy. During sharpening, you need to focus on the safety aspect to prevent injuries as well as damage to the edges. You should perform this maintenance at least twice a year. Below is a guide on how to sharpen your lawnmower blades safely to bring the best out of it.

1. Make Sure It is Off

Before you start sharpening the edges of the mower, make sure that it is off. In case it runs when removing the blade, you may get serious injuries. Remove the ignition wire from the spark plug and, if possible, remove the spark plug too. If the equipment is the cordless type, remove its battery pack. This action does away with the possibility of the motors accidentally coming on during maintenance. Also, drain the oil and fuel tank to avoid any spillages as you need to turn the mower upside down to access the blades.

2. Remove The Blades

You now focus on removing the blades to rejuvenate them. Here, you need to be extra careful as you may cut yourself. As such, you need proper toolkits to remove the cutter, such as gloves, pliers, and spanners of the right sizes. Turn the lawnmower over and secure the rotating head of the motor so that you can easily remove the blades. Use pliers or a spanner to loosen the bolt on the head of the engine to remove the blade. When removed, mark its edges for proper installation when done rejuvenating it. Do the marking at an area where the sharpener won’t erase the spot.

3. Cleaning The Cutter

Before sharpening, you need to clean the cutter for a smooth sharpening session. Clear it off the plant parts stuck on its edges and other dirt. If covered in rust, you need to use an anti-rust solution to help get rid of the oxidized area. A dry rug or sandpaper can also remove mild rust. For excessive corrosion, you may need a motorized sharpener or replace the blade.

4. Sharpening

There are two ways to go with sharpening, either using a file to sharpen lawn mower blades or use a machine manually. Using a rasp is the cheaper alternative to the two options though it may seem tedious. You need to clamp the cutter with a vice to hold it in place and use the file in a downward motion to sharpen the edges. A pair of industrial gloves would come in handy as they prevent bruises that may come from the contact of your skin with the metal. You can touch the edge once a while to see if it is sharp to your preferred degree. A face mask also comes in handy to prevent you from inhaling the metal pieces and dust from the sharpening procedure. You may need like three files for proper maintenance, though it depends on how robust the cutter is. For thinner blades, you won’t require a lot of filing tools like for a thick one.

5. Sharpening With A Machine

Grinding with a machine is very convenient if you want a quick exercise with a touch of precision. A bench grinder, a belts sander, or a handheld grinder can do the trick. Before proceeding to tackle the maintenance on your lawnmower blade, you need to observe precautionary measures. Get the right safety gear to prevent accidents when sharpening. Have a face mask plus some goggles to avoid the metal particles from getting into your mouth, nose, and eyes. Do not forget heavy-duty gloves to prevent bruises. Ensure the blade is on the proper grip in a vice and also have a bucket of water nearby. Use your grinder or any machine sharpener of your choice to run along the edge of the blade to make it sharper. Perform three to five strokes while checking on the precision of its cut. If the cutter gets too hot, remove it from the vice and immerse it into the bucket of water. This action prevents the blade from getting weak or bending. If the cutter is rusty, run the grinder across its width to get rid of the rust layer. Do it evenly to maintain its balance when you fix it to the motor.

6. Balancing And Attaching

According to Popular Mechanics, sharpening the blade does away with some metal layer and can lead to an imbalance of the cutter. Therefore, you need to check the leveling of the edge before fixing it. Try balancing it on a nail attached to its hub to see how it levels. If it is not level, try some minor sharpening on the heavier side until it achieves proper equilibrium. Apply a thin layer of oil or grease to its surface to prevent rust then reattach it to the motor. Ensure you fix it in the right ways according to how you marked it before removing it. Your lawnmower should be able to level your yard ideally once done with the maintenance session.


You should regularly service your lawnmower to get a perfectly edged yard during gardening. Sharpening its blades is one way to achieve this, and above is a guide on how to make the edges of your blade sharper. Aside from ensuring that the lawn mower’s cutter is sharp, it also removes rust, which may make the blade weak. Use a file or a machine, depending on your preference or available resources, to ensure your gardening equipment serves you well.

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