How to sharpen and clean electric hedge trimmer blades

How to sharpen and clean electric hedge trimmer blades

I’ve lost count of the number of times customers of mine come back to me after a year or two and complain that their hedge trimmer or pole hedge trimmer isn’t cutting as well as it used to. It’s happened so often, that I don’t even immediately look at the machine and instead ask ‘have you sharpened the blades since you bought it?’. The answer is nearly always ‘no’. to which my reaction is this-

If you are using garden tools that are made to cut things, chances are they will have blades, and if they have blades, those blades need sharpening from time to time or your tool won’t perform as it should. It doesn’t matter if it is a power tool like a chainsaw, brush cutter, or lawn mower, or something like shears, loppers, etc. You need to keep them sharp.

In this article, we will show you how to sharpen and clean electric hedge trimmer blades, so that you will get the most out of your machine, and not feel silly when you try to complain about it at your local DIY and gardening shop 😉

Why do hedge trimmer blades dull?

The answer to this is quite simple. You use a hedge trimmer for cutting through twigs and branches, and what do those contain? Sap, of course. Tree sap is very sticky and will cling to the blades of your hedge trimmer. Even though this is in very small amounts, it builds up over time, and this can cause your hedge trimmer blades to lose their sharpness. This doesn’t only happen to hedge trimmers but pruners, topiary shears, and other tools that cut through wood.
Dull blades make cutting much more difficult and this results in the motor having to work harder, and eventually causing damage to it through overheating. You don’t want your hedge trimmer to have a meltdown like this-

Different ways of sharpening electric hedge trimmer blades

In this article, we will look at three different ways to sharpen electric hedge trimmer blades, but in actual fact, you can use these methods for cordless hedge trimmers or petrol ones too.

The three methods we will explore are sharpening hedge trimmer blades with a file, Sharpening hedge trimmer blades with an angle grinder, and sharpening hedge trimmer blades with a Dremel tool. All are viable methods, so take a look at them all and decide for yourself which one best suits you.

Play it safe

When working with any sharp objects you need to wear gloves. Proper safety gloves are the best, but if you own a good pair of heavy-duty gardening gloves that are resistant to cuts, you can use them. Also, when sharpening hedge trimmer blades, especially with a grinder, it is not uncommon for metal shards to fly out and these could end up in your eye, so wear safety glasses.

Never attempt to sharpen an electric hedge trimmer, or any other bladed power tool, with the machine plugged in. Even if you have the machine switched off by its controls, the fact it is still connected to the mains means it’s a danger, so don’t risk it.

If you’re using a pole hedge trimmer, I would suggest removing the pole extension section before sharpening the blades as the sheer size of those tools are a trip hazard if left on the floor, and will make things difficult if you are sharpening on a workbench.

if you’re interested in what safety gear you should be wearing, check this out-

Don’t work with dirty tools

Before you sharpen the blades, you need to make sure that they are clean. There are many ways to do this, from simple soap, water, and cloth, to using a pressure washer on low power to blast off stubborn dirt.

Whatever way you go about cleaning your electric hedge trimmer, you need to be careful not to get water into the electric parts, or you can break the tool, or even cause yourself or others an electric shock. The safest way that I’ve found is to use a good cleaning solution and a good old wire brush, combined with a little elbow grease.

There are a few ways to clean hedge trimmer blades, so don’t worry if you aren’t exactly sure how to do it. There are plenty of videos you can watch on YouTube on the subject like this one too-

Line up the blades

To make sharpening easier, it is a good idea to line up the blades on your hedge trimmer before you start. As long as you are wearing a good set of gloves, you can do this by hand and it is quite easy to do. The reason for lining up the two rows of blades is so you can get into those notches easier, and ultimately end up with a sharper tool.

How to sharpen hedge trimmer blades with a file

Once your blades are clean, place the hedge trimmer on a table or workbench and then remove the bolt or screw that is holding the blades in place. With the blades free, place them into a bench vice, tighten it up, and then try to move it. If it moves, you need to tighten the vice some more.

Take your hand file and run it in a downwards direction across each cutting edge following the angle of it. Different blades have varying numbers of cutting edges, so this is something you need to check first. It is important that you only file in one direction and then lift the file back to the starting position. Filing back and forth is counterproductive and will only dull the blades more. This is a good thing to remember as it applies to sharpen any blade. It doesn’t matter if it is on a brush cutter, chainsaw, or even just a filleting knife

Uniformity is key when sharpening a hedge trimmer blade, so count out how many strokes of the file you give to each cutting surface and make them all the same. This will improve the performance of the tool. After you’ve finished sharpening, give the blade a coating of oil to prevent rust and corrosion in the future, and then reattach the blade using the bolt or screw you removed earlier.

Having nice, sharp blades will seriously improve the results of your hedge trimming sessions, and you’ll find that you get lovely, neat lines instead of crazy looking wavy tops. Just like this woman did-

Sharpening hedge trimmer blades with an angle grinder or Dremel

Although this method is a lot faster than using a file, it is also much easier to make a mistake and even ruin the blade completely, forcing you to buy a new one. So, if you’re not confident in your ability to use an angle grinder or Dremel, please stick to the filing method.

The first steps are the same as when sharpening with a file. Grab your tool box , remove the blade, secure it in a bench vice, and then check that you know how many cutting surfaces there are, and get the cutting angle figured out. if you don’t have a workbench or table, you might want to check out these saw horses that can be used with clamps or vices to secure things while you work on them.

Now you just grind the cutting surfaces in a downward motion, being very careful not to take too much material off. You will only need a couple of strokes with the angle grinder and try to be quite ‘light-handed’ with it. The same goes for using a Dremel tool, although some people find the latter easier to handle.

Again, it’s best to give the blades a good coating of oil before reconnecting them to improve the durability and longevity of the tool.

About Terry Smith

I’m Terry Smith from, a professional landscape designer, hobbyist gardener, and barbecue fanatic with 20 years experience building and restoring. So as you go through my site you'll watch me document some of the professional garden installs I make as well as the major projects I take on at home. While sharing those experiences and guiding you, I'll be recommending some great tools I use to enable this along the way so you can really buy in confidence. Always feel free to pop me a message:

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