Why is My Circular Saw Sparking? – How I Fixed It!

A Circular saw is a useful cutting tool for woodworking. When it uses, we can see some problems. Among them, sparking is a rare problem, and we can fix it easily. In this guide, you can study in-depth detail about reasons and solutions for circular saw sparking. So let’s see why does a circular saw is sparking?

Normally circular saw is sparking due to these reasons such as worn brushes, damaged windings, worn bearing, dust or debris, and unexpected metal cutting. You can fix this by changing carbon brushes on time and properly maintaining the circular saw on time.

Normally, the motor can spark to a certain extent, but it is not a problem. Sometimes it can be visible slightly. If the sparking is huge, we can clearly visible it and also noise will change due to this. So let’s see all in detail about circular saw sparking in detail with suitable solutions.

Worn Brushes

Circular saws are powered by DC motors. These are consist of brushes, commutator, windings, and armature. Brushes are used to provide the current to the armature. One side of the brush is connected to the power source, and other end is connected to the commutator.

When the commutator is spinning, brushes touch the commutator surface in order to provide power. As a result of this, brushes can wear due to heat and friction. Brushes are made with carbon because carbon is a good conductor.

Normally, we can see slight sparking from the brushes. When the brushes are worn, we can see clear and light speaking from inside the motor. So you should fix it asap when you see this. Else sparking will damage the inside winding and plastic materials easily.

After the brush is worn, the copper part will touch with the commutator. This will be a huge problem if you do not change the brushes on time.

Today, we can see brushless motors. Brushless motors are highly efficient than brushed motors. It is more powerful than brushed motors. So if there is a brushless option, you had better buy it. It will be a real solution for power and efficiency.

When should you change the brushes?
You should change the brushes when their length reaches 1/4 of their initial length.

Damaged Windings

When a current flows through a conduction wire, a magnetic field can be generated. This is the basic mechanism of the electric motor. In order to increase the power of the motor, a strong magnetic field is generated.

This can be happened by increasing the windings of the motor. These windings are covered with an insulation film. When this is damaged, the winding can be short due to inside current.

Due to heat, dust, debris, fil can be damaged. When it is damaged, we can see sparking during the spinning. So you should fix it asap when you see it the first time.

Read More About – Top 05 Circular Saw Problems and Solutions

Worn Bearings

Bearing is used to hold the arbor shaft. Usually, the bearing can be damaged due to continuous working without any repair or maintenance. Oil or grease should apply to the bearing in order to have a smooth rotation. When it is used for a long time without any lubricants, it can wear due to friction and heat.

Ultimately we can see sparking there. You can check this by moving the saw blade. You can hear abnormal noise from the motor. When you observe this, you had better replace the bearing as much as possible.

Dust Or Debries

When a circular saw is used for a long time, without any repairing or maintenance. It can spark due to the dust or debris inside. Normally, dust will not easily remove due to the applied lubricants and grease. As a result of this, these particles will make the sparking inside and we can observe chemical smoke inside.

Most debris can remain between the commutator spacing. So it should clean properly when you maintain the circular saw.

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Tom Mackency

Tom Mackency

Hi, I am Tom Mackency. It has been 10 years that I have been working as a professional woodworker since 2013. I am really enjoying my carrier by creating many kinds of projects in my workshop. But mostly I like for home improvement projects. Home improvement and DIY projects are the most interesting things for me. More than that, the coolest things are power tools. Those are very precious and efficient than a decade ago. So I try to introduce so many things about power tools, woodworking, DIY projects, home improvement and many more interesting topics here.