Why Is My Circular Saw Sparking?

Though circular saws are excellent tools to have around, they – like all machines – can sometimes be temperamental. A little sparking while cutting is regular, but if the sparks originate from the blade, that’s a red flag.

Your circular saw may be sparking due to a dull or unsuitable blade. If you use the saw on the wrong type of material, or if the blade isn’t compatible with the speed at which the saw is set, it will also cause the saw to generate heat – and sparks.

This article will reveal more about why your circular saw is sparking and how to fix or repair the problem. Continue reading to learn more.

1. You Are Using The Saw on The Wrong Type of Material

Tungsten carbide is a common material that you will find on the tips of most wood-cutting blades. The teeth are sharp and can quickly slice through lumber. However, this type of blade isn’t best for every job.

The tungsten carbide teeth will quickly become dull if you’re using your circular saw to cut through metal, concrete, stone, or other non-wood materials. When your blade is worn, it will create friction and heat up, which can cause the saw to spark.

How To Fix 

To fix your sparking saw, be sure that you use the proper blade when cutting through specific materials. 

Only cut materials suitable for the blade. Read the packaging if unsure what your saw blades can cut through. Most saw blades come with an instruction manual that will tell you precisely what they can – and cannot – cut. 

2. The Blade Is Dull

A dull or damaged blade can cause the saw to overheat, leading to sparks. 

If you use the saw frequently, the blade will dull over time. Even if you only use it occasionally, the blade can become damaged or chipped if it hits a nail or other hard object.

How To Fix

Take a close look at the blade’s edge. If you see any nicks or gouges, it’s time for a new blade. Then, listen to your saw as you’re cutting. A dull blade will produce a harsh, grinding sound, while a sharp blade will cut through wood with a clean ‘whistle.’

Consistently linger on the side of caution when it comes to your blade. A little care will go a long way, and your saw can run like new for years if you keep the blades sharp.  

Check out this article if you’d like to learn more about sharpening your saw blade.

3. The Saw Speed Is Too High 

If the saw is set to spin faster than the blade can handle, it will cause sparks. 

In addition, if the blade is too small for the depth of cut you’re attempting, the machine will have to work harder, prematurely dulling the saw.

How To Fix

Check the size of your blade and ensure it is compatible with the material you’re trying to cut. If you’re unsure, always err on the side of a smaller blade. 

You can also slow down the speed of the saw to give the blade more time to cut through the material.

4. Something Is Caught In the Blade

If a nail or piece of metal is stuck in your circular saw, it can overheat and cause sparks. 

This common problem is straightforward to fix, but if you continue trying to use the saw and don’t remove the debris, you might permanently damage your blade. 

How To Fix

If you think something may be caught in the blade, turn off the saw and check it immediately. Never attempt to remove an object from the saw while it is still spinning. Doing so could result in serious injury.

5. The Saw’s Commutator Brushes Are Worn Out

DC motors are standard in various power tools, including circular saws. These motors have brushes that help transfer the motor’s electrical current. 

Over time, these brushes can become worn out – and when they do, they can cause the saw to overheat and generate sparks. 

How To Fix

Suppose you suspect it may be the brushes causing the problem. In that case, it’s best to take the saw to a professional for further inspection.

A professional mechanic may replace, clean, or repair these brushes if they aren’t functioning correctly. 

6. The Saw Blade Is Dirty

If your saw is dirty, it may cause a variety of issues. The dirt and debris could block the motor, overheat the machine, and dull the blade. 

Sparks can result from all these problems, leading to fire risks and significant damage to your equipment.

How to Fix

If your saw blade is dirty, all you need to do is clean it. 

I like using a product called the AFMAT Cordless Air Duster (available on Amazon.com) to clean my saw. It does an excellent job of removing all the sawdust and is so simple to use!

Keeping your saw clean can avoid accidents and extend its lifespan.

How Can You Prevent Your Circular Saw From Sparking?

Using the right blade for your material and making sure it’s sharp are the best ways to prevent your circular saw from sparking. You should also set the saw to the correct speed. 

If you’re unsure what speed to use, consult the saw’s manual or ask a professional. 

Finally, be sure to keep the saw clean and free of debris. If there’s something caught in the blade, it can cause the saw to overheat and spark.

What Should You Do if Your Circular Saw Starts Sparking?

One of the essential safety features of a circular saw is its spark deflector. This component can prevent sparks from contacting the operator or anything else that may be flammable.

However, occasionally the spark deflector can become damaged or loose, which can cause the saw to produce sparks. If your circular saw starts sparking, you should turn it off and unplug it.

Then, inspect the saw for any damage to the spark deflector. If the deflector is damaged, it will need a replacement. You can try tightening it with a screwdriver if it is loose. 

Once you have corrected the problem, you can safely resume using your saw.


One way to help prevent your circular saw from sparking is to use the right blade for the material you’re cutting. Ensure the blade is sharp and adjust the saw’s speed to match the blade. 

You should also keep the saw clean and free of debris. If there’s something caught in it, the saw may overheat.

Finally, inspect the saw regularly for any damage to the spark deflector. If you find any damage, repair or replace it before using the saw again. Following these simple tips, you can avoid accidents and ensure your saw runs smoothly.

Damien Madeira

Damien has been doing woodworking for the last 5 years. He began as a hobbyist with hand tools and slowly worked his way up to own larger machines and mill rough wood into beautiful creations. While still considering himself a hobbyist, he has a passion for woodworking and enjoys working with epoxy as well.

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