Why Is My Circular Saw Spinning Backward [Troubleshooting Tips]

So, you get your working surface ready, put the materials in place, and shoot up the circular saw. Out of nowhere, you see the saw blade turning backward.

Suffice it to say that it’s not an unfamiliar situation for many of us. While the reason behind the issue may differ, many of us find ourselves wondering why our circular saw is spinning backward.Annoyingly enough, there’s no way to use the saw until the problem is alleviated.

This discussion will seek to figure out the culprits behind this problem and help you troubleshoot it. In addition, it’ll include some possible solutions to get the saw up and running perfectly.

Why is my circular saw spinning backward

First Things First — Is It Really Moving Backward?

Hear me out. If you know your way around circular saws, you’d know if the blade’s correctly installed. However, for many beginners, this is a pit for confusion.

The most common way of explaining the direction of a saw blade is according to clocks. But that can cause some confusion, as something that’s turning clockwise from one side would seem counter-clockwise from another.

Therefore, let’s first make sure whether the blade is turning backward. Instead of wondering about clockwise directions, see if the blade’s teeth are moving upwards — or in your direction when using it.

If it has been installed correctly, you should also see an arrow on the blade indicatingthe direction it should turn in. If that’s not the case and the blade’s teeth (assuming it has them) are not digging into the material, then the saw blade is turning backward.

With that confirmation, let’s move on to the brass tacks.

Why Your Circular Saw is Spinning Backward

We will divide the issue into some potential categories. This allows for easier troubleshooting.

Incorrect Blade Installation

An incorrectly installed blade is the most common reason behind a saw turning in the opposite direction. Hence, our first step is to check whether the blade has been installed correctly.

Many assume that they should see the label side or vice versa to determine this. But since we have blade-right and blade-left saws, it’s tough to judge the correct orientation.

See if the blade is turning upward or toward you, the user. Another way of thinking is that the bladeshould go down on the material with its sharp teeth. Otherwise, a blade rotating upward with so much pressure would push the materials upward.

Another way is looking at the saw’s blade cover, which usually has a mark to show which direction the motor turns. With that information, you can install the blade to move in the same direction.

If the installation is incorrect, turn the saw off, remove the saw blade, and install it correctly.

A Scuffed-Up or Bent Blade

The blade is designed to turn in one direction and handle the resistance. Hence, all of its parts and teeth should maintain uniformity and stay in place.

But if the blade has its teeth bent, the bent portion increases the resistance on the blade and can ruin its balance. If the opposite force is too much for it to handle, the blade can turn in the wrong direction.

Check whether the saw blade is in good condition, and replace it if it isn’t.

Motor Brush and Insulation Troubles

The brushes (assuming that it’s a brushed motor) are responsible for conducting power between the wires within the motor. Faulty brushes can affect the motor’s power delivery, sometimes causing it to turn backward.

After a motor has been wound, its windings are insulated to protect it fromoutside elements and reduce friction. This can also get scuffed up over time, once again affecting the power delivery and making the motor rotate backward.

Troubleshooting the motor is slightly trickier. While you could look for visible worn-out components and the winding insulation, you may have to disassemble the motor further to take a closer look. You might have to replace the deteriorated parts.

Another possibility is that the gears are not aligned properly. If that is the case, the additional resistance produced can force the saw to reverse its rotation. Fixing this does require some technical know-how, though.

Short Circuits or Crossed Wires

If any unintended component comes between the motor’s connections, it can result in a short circuit. This can also cause the motor to rotate backward. One of the most common reasons behind this can relate to heat build-up.

If there’s too much heat within the motor, it can cause insulations to melt. Consequently, they fail to prevent any unwanted connection points, altering theelectric current’s path. Strip connections can also be the culprit, where the terminals don’t have sufficient protection from short circuits.

Hence, check the connections and wirings to see if they have sufficient insulation between them.

This issue may also stem from crossed wires. It’s when the wires connect in the reverse order instead of the standard one — resulting in opposite polarities.

The direction of the flow of current is crucial (whether it flows from negative to positive or vice versa). Across between the connections can alter the power supply to the motor and make the saw turn backward.

Once again, check the connections and see which ones can potentially result in reversed polarization. You can look at the resistance using a multimeter to see if the pole is crossed.

Note that dismantling the motor can void your warranty. Or if you’re not comfortable doing it, it’s better to have professionals do it anyway.

Defective Belts or Pulleys

Belts and pulleys play a crucial role in transmitting the power produced by your motor, and they can wear out with time. The belt is more likely to show signs of wear and lose its ability to work.

On the other hand, the pulleys in a motor are more likely to result fromdirect physical damage. Issues like excessive friction may prevent them from moving as intended, making them rotate backward. You need to physically check these components to see if they’re faulty or worn out, however.

Logical Errors

Circular saws rely on a combination of sensors and logical processors, which are then dictated bythe firmware. For more updated saws, this reliance grows even higher.

It may help prevent overheating, overloads, or even the battery levels of a saw. If the sensors that provide such information are faulty or if there are errors in the processing, it can cause issues for the saw.

Double-check if you’ve turned any settings to anything suboptimal, like the torque (or even the speed, if your saw has that capability).

Additionally, make sure that you’re not applying too much force or putting the saw through too much load.

These are some of the core reasons behind a circular saw’s blade turning the other way around. Typically, the culprit is usually related to the blade, motor, orits wirings, so it’s better to begin in that order.


Instead of wondering why your circular saw is turning backward, you could try out some basic troubleshooting. More often than not, you may be able to identify the main reason yourself. Remember not to fiddle with the saw if it voids your warranty.


My name is Michael M. Militello, and I want to help you find the right tools and the best products for your next project! As a professional tool expert here in Houston, TX, With my vast tool experience, I can help you choose the right brand, model, and size for the job. Please feel free to contact me with any questions you may have. You can reach me here on my blog and also on Facebook, Twitter , and Pinterest. I look forward to hearing from you!

Leave a Reply

Your email address will not be published. Required fields are marked *