How To Sharpen a Brush Cutter Blade

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Brush cutter blades get dull over time. That’s not a huge surprise. Even the best brush cutters can’t fight against branches, rocks, and hard ground, especially when you’re regularly using them to clear rough terrains, such as golf courses or areas with lots of scrub and thorn bushes.

So definitely, you will need to learn how to sharpen a brush cutter blade; otherwise, you will experience disappointments. However, many people see sharpening blades as an arduous DIY task done explicitly by experts, which is not always the case. It is as simple as passing the blade severally on a metafile or grinder until it achieves maximum sharpness.

So you don’t necessarily need to replace your blade if you notice it is slow when cutting through bushes. You only need a few simple tools at hand and a guide to help you through. Keep reading to learn more about these tools and, ultimately, how to sharpen your blade.

Essentials Tools To Have When Sharpening Your Brush Cutter Blade

When sharpening blades, you need the right tools at hand. And in this case, a file or a grinding wheel will work great. For the file to serve you at its best, you’ll need a flat surface to use as a reference point and a vice to hold the blade in place.

Similarly, if you’re using a grinding wheel, you will need an adjustable work light to monitor your progress and avoid overfilling. Having an angle grinder at hand would also make your work easier.

Now that we’ve identified the basic tools you should have at hand let’s start sharpening our blade!

How To Sharpen a Brush Cutter Blade

We all know proper maintenance of a brush cutter will generally improve its performance and lifespan. However, proper care goes beyond general cleaning after use. For instance, regular sharpening of the brush cutter blade is also an essential aspect of maintaining your tool. And, of course, who doesn’t enjoy working with a top-performing tool?

Sharpening your brush cutter blade will make things easier for you. Here is how you can effectively sharpen your blade in a few minutes.

1. Disconnect the Spark Plug

Before you even think about sharpening the blade, first disconnect the spark plug. The spark plug is a small plastic piece that’s designed to keep the mower from running during repairs to minimize injury risk.

Once you’ve disconnected the spark plug, don’t wrap the cord around the plug itself—it could lead to premature fraying and damage over time. Instead, take a look at your brush cutter and determine where you’d like to store your spark plug while working.

Read: How to remove rotary cutter blades

2. Remove the Blade

You will then have to remove the blade from your brush cutter. You will need first to locate the bolt that holds the blade in place to do this. Once you locate it, use an adjustable wrench to unscrew and remove it carefully.

The blade should be able to separate easily from the brush cutter once the bolts have been unscrewed.

3. Clean the Blade

After removing the blade, clean the dirt in it. Most of it will be in the form of stuck-on grass and weed clippings. This debris may interfere with sharpening, so make sure you properly clean the blade.

In essence, if you have a wire brush, use it to scrub off the blade and clear all the grass clippings.

Read: Heavy duty brush cutter blade

4. Check the Cutter Blade Condition

After cleaning the blade, you should then check its condition. From a distance of about half a meter, it should be easy to see if there are any deep scratches on the blade. And in case you notice your blade is broken, cracked, or chipped, then prepare yourself to bear the cost of a new blade. 

And as mentioned above, to sharpen a brush cutter blade, you’ll need a grinder or metal file. However, whichever tool you choose will depend on your sharpening needs. If it’s blunt, but otherwise in good shape, you may only need to use a file to get it back to normal. 

5. Sharpening the Blade

  • Manual Sharpening Using Metal Flat-File

Begin by securing the blade in place. So you will need to hold it tightly and securely such that you can run the flat file across without fear of slipping.

Additionally, you will need to angle the flat file properly in relation to the blade to get an even cutting edge on both sides. We recommend that you use a manual file guide to maintain the correct angle while filing.

Basically, you will need to run the metal file across the blade’s cutting edge severally on both sides to achieve maximum sharpness. Keep going until you notice the end of bluntness.

  • Using a Grinder

A grinder is one of the simplest tools you can use to sharpen your brush cutter blade. It is the fastest. Good thing; it will sharpen both sides of your blade uniformly and evenly without compromising the sharpness quality.

First, put on gloves and safety glasses, as you will need to protect your hands and eyes from flying chips or sparks.

Next, you have to place the grinding wheel on the shaft of an electric bench grinder. Be keen and ensure the grinding wheel is designed explicitly for sharpening blades—the softer wheels used to sharpen knives won’t last long against a brush cutter blade.

Additionally, ensure that you have plenty of space to work with since you will be making broad sweeping motions with your arm. Begin by resting the blade against the grinding wheel at approximately 45 degrees, then run your arm back and forth along its length.

Ultimately, keep your hand steady as you move forward and backward with each pass. Then repeat this process severally and watch out for results.

6. Balancing

Now that you’ve sharpened your blade, you will have to check for balance capabilities. Hold the blade with the center hole over a nail or screwdriver head to test for balance. The blade should hang level. If it doesn’t, you’ll need to grind more from the heavy side until it balances.

Read: What are high lift mower blades?

Safety Precautions To Take When Sharpening

Sharpening a brush cutter blade is a pretty easy task, although it can be dangerous at the same time. Here are some safety precautions you should take to stay safe when sharpening a brush cutter blade:

  • Always wear proper eye and hearing protection when sharpening your blade.

The high-speed rotation of the blade will create sparks, which could potentially damage your eyes if not protected. The same is true with ears, as the metal blade will produce mysterious noises while sharpening.

  • Secure the blade so it doesn’t move while working on it.

If the blade isn’t secure and turns while you are sharpening, it may damage the brush cutter chain. So always secure the blade before sharpening.

  • Make sure the blade is cool before sharpening.

Give your blade time to cool before sharpening- particularly if you were using it and suddenly it became dull. This is because, once you sharpen it when hot, the chances of cracking or breaking are high, forcing you to buy a new blade that may prove costly.

  • Finally, don’t place your fingers on the blade.

You may accidentally cut your fingers as you sharpen the brush cutter.

The above steps are fairly simple. So with the right tools and some basic knowledge, you’ll be able to sharpen your brush cutter blade with relative ease. In turn, you’ll be able to work longer with your machine without bearing the loss incurred with regular blade replacements. Ultimately, your brush cutter will always be ready to serve you at its best.

Our top pick for blade cutter blades is Forester Chainsaw Tooth 9″ Brush Blade, which is versatile and at its best when cutting small shrubs and trees.

Read: Using car ramps to change mower blades