How to Sharpen Reel Mower Blades

How to Sharpen Reel Mower Blades Featured Photo

Reel mowers, also called cylinder mowers, are one of the most commonly used devices to maintain lawns. These reliable machines have been around for hundreds of years and are one of the oldest types of lawn mower with the earliest model dating back to 1830. A reel mower usually has two pairs of blades that are helical in shape and a main horizontal cutting bar at the rear.

I love that they are quiet and don’t use any gas, plus these blades are built to be sturdy and retain their edge for longer. A well sharpened reel mower is capable of making clean cuts on blades of grass which helps the grass heal faster and grow back thicker. 

Eventually though, these blades are going to dull and make less clean cuts over time. The good news is, you can sharpen the blades instead of buying new ones or switching to a new reel mower.

In this article, I’ll be going over some easy methods that you can use to sharpen the blades of your reel mower. If that sounds dangerous, don’t worry because the steps as easy to follow as possible and by the last step, your reel mower will be good as new. 

Table of Contents

Important Factors to Consider

Before we get to how to sharpen dull mower blades, let’s go over some important factors first. 

How does a reel mower work?

A reel mower may look pretty straightforward but there’s a lot of moving parts and gears involved. Without getting too technical about it, let’s break down what happens when you start pushing a reel mower. 

The first things that’ll move when you start pushing are the wheels and the axle that holds the helical blades. Not only does this move the reel mower forward, this also feeds grass to the helical blades that scoop the grass towards the cutting bar located to the rear of the assembly. The rotating helical blades pinch the grass against the edge of the cutting bar in an almost scissor like motion which is why the blades of grass are sliced so cleanly. The grass clippings then fall into a collection pan, bag or back to the ground. 

How does a reel mower work

Reel mowers are manually powered but the helical blades (replacement image needed)
will spin much faster than the wheels. This is thanks to a number
of gears that you can find behind the wheels. These gears make the reel mower cut faster while lessening the amount of resistance felt by the users as they push along. They are still quite a bit more work than a gas powered push mower.

Sharpening Options

Metal File

Metal files are a popular choice used to sharpen a reel mowers blades. These files are typically 5 to 12 inches long and provide enough reach so you don’t have to disassemble the whole reel mower. Metal files have two sets of teeth on either side with one side being rougher than the other. The teeth on a metal file are very small but durable. Metal files are commonly used in workshops or garages and are ideally used for sharpening, deburring, smoothen surfaces and shaping materials like wood, metal or plastic. These are great multi purpose tools that you can use for other DIY projects or to maintain other machines or appliances as well.

Metal File

Reel Mower Sharpening Kit

If manually sharpening reel mower blades sounds like too much of a chore for you, don’t worry because there is an alternative that might even be better.

American Lawn Mower Company SK-1

Thankfully, some manufacturers had the whole sharpening thing thought out and designed kits specifically to make the job of sharpening reel mower blades easier. These usually
consist of a brush, a compound for sharpening and a hand crank.

The sharpening compound can be used for any reel mower blade

but the hand crank may differ in size depending on the brand. Manufacturers usually have a list of compatible brands that you can use the sharpening kit on. Some manufacturers even sell the sharpening kit alongside the reel mower so be sure to keep an eye out on those deals.

Reel mower sharpening kits speed up the whole process but using one does require that you take apart parts of the reel mower first. We’ll get into the details down below.

How To Sharpen Reel Mower Blades Guide

Instructions for Using a Metal File

Step 1: Preparation

It’s highly recommended that you clean off any debris like pebbles, grass clippings or dirt on the blades before getting to sharpening. Do this with the help of a wet piece of cloth. Wipe down the cutting bar edge and helical assembly carefully but thoroughly till all the debris is gone. You could also use a stiff wire brush to remove stubborn stains or stuck debris. Coarse sandpaper is also a good choice to use here. At this stage, you should also remove the handles to make accessing the blades easier.

Step 2: Safety

Before getting to business, you’re going to want to ensure that the reel mower does not move during the process. You should also avoid wearing loose fitting clothes and jewelry like watches. We recommend you position the reel mower on its side on top of a table so that you have access to the full length of the helical blades. After that, you could secure the reel mower by wedging a thick enough stick, such as a broom handle, through the mower’s helical blades. This should jam the mechanism and stop it from turning. We also recommend that you wear gloves and some eye safety during the whole process of sharpening.

Step 3: Filing

With the reel mower in place and helical assembly secure, you can now begin filing. This is pretty straightforward. Using the rougher side of the file first, angle the file on the cutting edge of the first helical blade and begin filing about 5 times along the length of the helical blade. You’ll have to carefully rotate the blades and secure them again each time. Repeat this for all of the helical blades. Afterwards, flip the file over to the smoother side and repeat the process.

Step 4: Finishing Touches

After you’re done filing all the helical blades, clean up the edges with a damp cloth. Test the reel mower on some grass and see if the blades are sharp enough to your liking. If the blades are not sharp enough, or hear a loud scraping sound, repeat the sharpening process. You could also spray lubricant directly on the screw hole and reel screws to make it rotate smoother and resist rust.

Here’s a quick video demonstrating how to sharpen a reel mower with a file.

Instructions for Using a Sharpening Tool Kit

Step 1: Preparation

Before applying the compound, you should begin wiping down the helical blades to remove any debris. You can use a damp cloth, sanding paper or even a wire brush to get rid of stubborn stains or stuck dirt. Next, remove the handle and place the reel mower on top of a table. During the preparation phase, you should also remove one of the wheels and adjust the height of the helical blade assembly. 

Step 2: Adjusting the Height

First of all, you’ll want to check if it even needs adjustment. Do this by spinning the helical blades. While spinning, the blades should be brushing lightly against the edge of the cutting bar and make a light scraping or clicking noise. If you hear screeching or if the blades are not making contact with the cutting bar at all, you’ll have to adjust the blades closer. In order to adjust the height of the assembly, use a socket wrench or screwdriver to tighten or loosen the bolt (or screw) on either side of the assembly. Take note that there are typically 4 bolts or screws that you need to adjust. 2 on either side of the helical blade assembly and 2 on the cutting bar that need to be adjusted as well. Adjust them until they are in an appropriate position and are making enough contact with the cutting bar.

Step 3: Applying Sharpening Compound and Sharpening Process

Using the brush that comes with the kit, apply the compound along the edges of the helical blades. You’ll want to put a generous coating per blade. Afterwards, on one of the wheels that you removed during the preparation phase, you would need to find the drive shaft. This is where you are to place the hand crank. When the hand crank is in, carefully turn it in a counter clockwise direction or in the opposite direction of how the helical blades normally spin. Do this for around 5 to 10 minutes. The blades should be sharpened if they are polished. You can test out the sharpness by slowly spinning the blades and pinning a piece of paper or a leaf between the blades and cutting bar. You can always repeat the process (replacement imade needed)
if you feel it needs to be sharper. 

Applying Sharpening Compound and Sharpening Process

Step 4: Finishing Up

Once the blades are sharp enough, wipe off any remaining sharpening compound and reassemble the reel mower. You can also wash it off with water and test run it through some grass.

Here’s a quick video demonstrating how to sharpen a reel mower with a sharpening kit.

Best Metal File for Sharpening Reel Mower Blades:
WORKPRO W051002 Flat File

Key Specs & Features:

  • Overall Length: 17.5 inches
  • File Length: 10 inches
  • Material: Alloy Steel
  • Weight: 10.2 oz
  • For both wet and dry applications
  • Coated double cut teeth
  • Anti slip rubber grip
  • Multi-purpose tool
WORKPRO W051002 Flat File Overview


This multi-purpose flat metal file by WorkPro gives users more of a grip while working along with a durable design that can be relied on to get the job done.

The WorkPro W051002 metal file features a double cut design on either side making it great for deburring and sanding projects alike. The file itself is made with hardened steel and measures 10 inches long, giving users a lot of reach and surface area to deburr or sand surfaces. This metal file comes with a anti-slip rubberized grip that fits comfortably in the palm of one’s hand and is designed to be ergonomic.

The WorkPro W051002 metal file is ideally used to
sharpen, smoothen, deburr and shape materials. When used on blades such as those on a reel mower or lawn mower, the W051002 performs great and gives users more than enough reach to sharpen the whole length of the blade efficiently.

Best Sharpening Kit for Reel Mower Blades:
American Lawn Mower Company SK-1

Key Specs & Features:

  • Hand crank included
  • Brush included
  • Manual included
  • Compatible mowers: Great States, American Lawn Mower, Earthwise & Scotts
  • Compact DIY kit
American Lawn Mower Company SK-1


This sharpening kit from American Lawn
Mower Company provides users a quick and easy
method to sharpen lawn mowers blades and sharpen reel mowers blades alike.

The American Lawn Mower Company SK-1 reel mower sharpening kit comes complete with a brush, grinding compound and a back lapping hand crank. This is a DIY kit that’s compatible with a lot of well known brands such as Scotts and Earthwise. Using this kit saves users time and effort by being easy to apply and store afterwards. 

The SK-1 kit is a great choice for those reel mower owners looking for a way to better maintain and keep their blades in the best shape. 


Q: Which sharpening method is better?

A: In our opinion, a sharpening kit would be the way to go. Using a sharpening kit makes the job more efficient and more convenient as well. The only downside being that there are some hand cranks that aren’t compatible with some brands of reel mowers. Metal files are a good alternative however, especially if you have one already but will take longer and require some endurance. A power drill with a sharpening attachment can help, but you need to be careful not to wear down the blade too much.

Q: How often do I need to sharpen the blades?

A: This depends a lot on how often you use the reel mower, how long each session is and how long you let the grass grow before trimming. On average though, we estimate you’ll have to sharpen the reel lawn mower blades every year to keep the beveled edge sharp. Make sure to sharpen all the blades and check that the bed knife (or bedknife) is perfectly flat.

Q: Do reel mower blades rust?

A: Like all metal gardening tools, it will eventually rust. There are some solutions to this such as drying them off properly after every use with a towel, using WD40 on the joints and using rust resistant paint coating. If you don’t let it get too bad, some metal finishing sandpaper is often enough to just knock a bit of rust off your sharp blades.


And there we have it, how to sharpen the reel mower’s blades and the tools you need to get the job done. We hope that this article taught you a thing or two about maintaining reel mowers and that you leave here more informed and become a better reel mower owner. Happy mowing!