How To Sharpen Mower Blades – All You Need To Know

The Tricks for Doing It Right the First Time

I don’t know about you, but sometimes I just really wish that lawnmowers came with blades that sharpen themselves!

Truth is:

If you own a lawnmower, YOU are responsible for keeping the blade sharp. Unless off course you want to do double the work with a blunt blade!

I’m not going to write a novel about the process, because once you get the hang of sharpening your mower blades, it’s going to be child’s play.

How to Sharpen Mower Blades – D.I.Y

The process is really straight forward and uncomplicated. Here are your 10 steps for sharpening the blades of a lawnmower.

Step 1:

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Take out the blade. This is easy. Just remove the nut that attaches to the mower.

Step 2:

If you can see visible rust on the blade, be sure to clean it with steel wool or a steel brush.

Step 3:

Secure the blade by using a vice to clamp it down and make sure you’ve got a solid work surface

Step 4:

Take a file and run it down the cutting edge of the blade while sticking to the angle of the blade.

I just use a Stanley 21-106 8-Inch Mill Bastard File.

Stanley 21-106 8-Inch Mill Bastard File

Stanley 21-106 8-Inch Mill Bastard File

Step 5:

If you’re having a hard time to hone the damaged blade, consider using a bench grinder, or better yet, just take it to a professional.

Step 6:

Run the blade perpendicular to a grinding wheel so that you get rid of nicks and gouges.

Since I’m not always in the mood to use my grinder, I sometimes just attach my Multi-Sharp R305 Mower Blade Sharpener to the front of my electric drill.

Multi-Sharp R305 Mower Blade Sharpener

Multi-Sharp R305 Mower Blade Sharpener


Step 7:

Now hold the blade at its natural angle and grind the length of the blade until its sharp.

Step 8:

Balance the blade from the center point. You can use a nail for this but I highly recommend using a Blade Balancer to ensure that’s it’s correctly balanced.

Personally I use the Oregon Lawn Mower Blade Balancer

Oregon Lawn Mower Blade Balancer 42-100

Oregon Lawn Mower Blade Balancer 42-100


Step 9:

If you’re struggling to balance the blade out, grind the blade a little more on the heavier side – please don’t grind off the surface area of the cutting edge!

Step 10:

Sit back. Revel in you accomplishment and then reattach the blade to the mower.

I am sure that you will find these steps easy for learning how to sharpen mower blades. 

A few lesser-known tips for lawnmower blade sharpening:

  • This sounds kind of obvious, but if you make it a priority to regularly sharpen the blade of your mower, you won’t have to work as hard to get a good edge on the blade.
  • Keep in mind that power grinders can weaken blades due to the heat they transmit. Make sure you’re quenching the blade (cooling it down in water) throughout the process to prevent overheating.
  • As for the sharpness you’re trying to achieve, always aim for “butter knife” sharp and not “razor blade” sharp. Grind the edge too sharp and the blade will get dinged by pebbles.
  • If you don’t have a file or grinder on hand, you CAN use coarse grit sandpaper to just touch up the sharpness of the blade. This will NOT work for big issues like dings, but it cleans up the edge pretty good.

And those are the essential tips you need. Remember – as long as you have a vice, a grinder and a metal file, you’re good to go.

The Best Tools for Sharpening Lawnmower Blades

Okay so while the standard vice, file and grinder will always be a go-to option for me, some of you might want to invest in a specific tool that’s going to take the hassle out of the process.

For that reason alone, I went out and tested some of the tools out there so that I can show you what they do and don’t do.

Here are my thoughts: 

Dremel 100-LG Lawn and Garden Rotary Tool Kit 

I scored it: 4 out of 5 stars

I actually enjoyed this nifty little tool for its versatility. It will slice anything from metal to light wood and plastic. It also grinds and sharpens furniture and appliances AND comes with a sanding fitment for smoothing edges. Essentially, this is MUCH more than just a mower blade sharpener.

The Pros

  • It’s an all-in-one tool
  • It comes with a garden tool sharpening attachment, a lawn mower sharpening attachment and a chain saw sharpening attachment.
  • Its lightweight and easy to use 

The Cons

  • You’re not going to be able to use it for extended periods of time without letting it overheat
  • It’s not cordless, so you’ll have to be near a power supply when using it
Dremel 100-LG Lawn and Garden Rotary Tool Kit

Dremel 100-LG Lawn and Garden Rotary Tool Kit


Smith’s 50119 Mower Blade Sharpener

I scored it: 3.5 out of 5 stars 

For just a pinch less than the price of the Dremel, you get the Smith’s Mower Blade Sharpener. It’s a great tool for keeping your blades in top condition. I really liked the fact that it was easy to use and the fact that it takes literally minutes to get the job done.

The Pros:

  • The weighted metal head lends a feel of durability and also makes the process quicker and easier
  • The rubber hand and finger grips means you get the most comfortable grip while you’re sharpening the blade
  • The oversize handle is ideal for when you’re wearing gloves

The Cons:

  • The sharpener isn’t going to work for heavy blades
  • I’m not fond of the design – plastic covering and no way to prevent the tool from touching the blade equals a recipe for disaster
  • It’s not going to keep a steady and consistent sharpening angle
Smith's 50119 Mower Blade Sharpener

Smith’s 50119 Mower Blade Sharpener


Accu Sharp 060 GardenSharp Tool Sharpener 

I scored it: 2 out of 5 stars 

The manufacturers say that this funky looking sharpener will tackle anything from mower blades to pruning shears, shovels and scythes and put the edge back on things. I’m not too sure. It’s not suitable for the sharpening of mower blades in my opinion, but I suppose it’s going to do a fine job for shears?

The Pros:

  • Comes with a full length finger guard
  • Comes with a reversible diamond honed tungsten carbide blade for sharpening your blades
  • The materials used for construction are rust and corrosion resistant

The Cons:

  • This tool didn’t actually work for sharpening lawnmower blades.
  • Getting the angle right for sharpening blades is almost impossible, and the instructions that come with the tool make things much worse since it’s not very well written
Accu Sharp 060 GardenSharp Tool Sharpener

Accu Sharp 060 GardenSharp Tool Sharpener


And that’s a wrap folks. Be sure to check back in soon where I’ll be sharing my experiences and knowledge with you about why it’s OKAY to use a cheap knife sharpener.

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