How To Fix Orbital Sander Slows Down? (8 PROVEN Fixes!)

orbital sander slows down

The orbital sander is a woodworking power tool that uses to achieve a super nice and smooth surface for various woodworking projects.

Usually working with the orbital sander is fun and easy. But things can get messed up when it’s not working properly. Likewise, let’s find out, what should we do if, the Orbital sander slows down

Orbital sander slows down due to torn cords, not having a good power source, the motor or rotor being damaged, the shaft being rusted, clogged dust and rust, and damaged bearing. Fix the orbital sander slow down by fixing torn cords, cleaning, and replacing brushes and bearings, fixing the motor and rotor, and ensuring the power source.

But there’s more to know about fixing orbital sander slows down.

So, in this article, we’ll examine deeply why does orbital sander slow down, and how to fix that with easy tips and troubleshooting tips.

Plus, I’ll answer some frequently asked questions as well.

Just keep reading!

Why Does Orbital Sander Slow Down?

The orbital sander slows down due to various issues. There’re separate reasons for slowing down of electric orbital sander and pneumatic orbital sander (air sander).

If your orbital sander is under warranty period, better to send it to the repair center if the slowing down issue happens not because of the dust or dirt which can easily fix by cleaning.

Here’s the list of reasons that cause orbital sander to slow down,

  • Torn cords
  • Clogged dust and rust
  • Damaged bearings
  • Not having a good power source
  • Damaged motor
  • Damaged rotor
  • Shaft is rusted
  • Wrong assembling

Some of the above reasons for slowing down are varies on the type of orbital sander.

An electric orbital sander runs on electricity and a pneumatic orbital sander (air sander) runs on air power.

Both of them have separate reasons and common reasons for slowing down.

For a better understanding refer bellow the table to find out why the orbital sander slows down based on the sander type.

Electric Orbital SanderPneumatic Sander (Air Sander)
Torn cordsRotor is damaged
Not having a good power sourceShaft is rusted
Damaged motorClogged rust and dust
Clogged rust and dustDamages bearing
Damages bearingWrong assembling
Wrong assembling 

Most of the above reasons that cause the orbital sander to slow down can be easily fixed by cleaning or replacing the specific parts with new ones.

So, let’s discuss each of the above reasons separately for both electric and pneumatic orbital sanders and find out how to fix that to make the orbital sander run properly.

1. Torn Cords

Torn cords can slow down the electrical orbital sander. There’re lots of cords inside the electrical orbital sander that uses to transfer power between components.

If any of the orbital sander cords get torn off, that will slow down the sander and dramatically reduce the machine’s efficiency.

First, you need to check the cords of the orbital sander that connect to the power supply for any damaged or whether it is torn.

If there’s any damage to cords, it will build up high resistance during the electricity is traveling through the cord.

Due to the high resistance created in the loose joint, electricity flow will be interrupted, and the sander will begin to spin slowly due to low power.

Likewise, when the cords are torn, current will not pass through the torn area and the sander won’t work. A high resistance will build up and cause a decrease in power flow. This will result in the sander slowing down.

So, let’s find out what are the reasons that cause torn cords.

Why Do Cords Tear?

Orbital sander cords are torn due for several reasons. When your orbital sander slows down, check whether cords are damaged or torn to find the reason for that.

Here’re the reasons that cause cords to tear,

  • Excessive heat or cold
  • Heavy use
  • Spill chemicals
  • Excessive power flow
  • Age
  • Insect or animal attacks
  • Weather conditions
  • Abrasion of the sheath

So, let’s find out how to fix torn cords to get rid of the orbital sander slows down.

How To Fix Torn Cords?

Here’re the simple steps you need to follow to fix torn cords and fix the orbital sander slowing down the issue.

  1. Disconnect the orbital sander from the power source.
  2. Check the power cord for any torn and damaged areas.
  3. Use a multi-meter to measure the resistance between the several points of the cord.
  4. If the resistance is high between two points, the break or tear is in between them.
  5. Tighten the loose joint or replace the cord with a new one.

Tip: Better to use a smaller length cord for the orbital sander to prevent it from breaking or tearing due to high resistance. Because when the cord length is high, the resistance build-up is also high.

High cord length causes the power supply to get less current.

Now you know how to fix torn cords to fix the orbital sander slows down the issue.

Let’s focus on how dust and rust affect the slow spinning of the orbital sander.

2. Clogged Dust and Rust

Clogged dust and rust can slow down the orbital sander. Dust and sand can affect the efficiency of both electrical and pneumatic sanders (air sanders).

Brushes of electrical and pneumatic sander can get affected by dust and rust. They clog in the brushes and slow them down.

Dust and rust damage the brushes and reduce their efficiency drastically.

On the other hand, dust and rust may get deposited on the speed controller as well.

The speed controller of the orbital sander is useful to increase the power when the pressure is increased and decrease the power accordingly. It is the component that controls the speed.

Due to the dust and rust clogged in the speed controller, it gets damaged and failed.

With clogged dust and rust speed controller of the orbital sander cannot work efficiently and it causes the orbital sander slows down.

Dust and rust prevent the speed controller from increasing the power when the pressure is increased.

Dust and rust cause components of the orbital sander to retain heat and make the machine difficult to dissipate heat.

Why Does Dust and Rust Clog?

There’re so many reasons dust and rust clog inside the orbital sander which makes it slow down.

This need to be fixed right away because the poor efficiency of the component can do significant damage to the whole sander.

Here’re the main reasons for the clogging of dust and rust inside the orbital sander,

  • Dust particles with opposite charges attract and stick-on electrical orbital sanders
  • Poor maintenance
  • Not cleaning the orbital sander regularly

So, let’s find out how to fix clogged dust and rust to get rid of orbital sander slows down.

How To Fix Clogged Dust and Rust?

  • Clean the orbital sander regularly with a clean cloth
  • Dissemble the orbital sander and clean the brushes
  • Replace brushes with new ones
  • Take nit comb and drag it across the sander’s pad vigorously
  • Maintain the orbital sander properly and store it in a dust-free environment
  • Replace the speed controller with the new one

Now you know how to fix clogged dust and rust to fix the orbital sander slows down the issue.

Let’s focus on how damaged bearings can affect the slow spinning of the orbital sander.

3. Damaged Bearing

Bearings are one of the main components of an orbital sander. When the bearing gets damaged due to various reasons, the orbital sander slows down or won’t work at all.

The main bearing is located bottom of the orbital sander which keeps the disc rotating. Other bearings inside the orbital sander support the bottom bearing by rotating.

If one of the bearings or several ones got damaged due to rust, dirt, dust, dent, or age, they won’t spin properly, and the bottom bearing won’t rotate properly.

Bearings need to spin freely for the efficiency of the orbital sander. If they don’t spin freely, the orbital sander slows down over time.

This makes the orbital sander slows down and you need to fix this issue immediately before other bearings also get damaged due to the poor rotation of damaged bearings.

Why do Bearings Get Damaged?

Bearings can get damaged due to so many reasons. If any of the bearings get damaged somehow, all the others may get damaged since they all are interconnected with rotation.

Here’re the main reasons why bearings of orbital sander get damaged,

  • Dust and dirt inside the bearings
  • Long exposure to high humidity
  • Water damages

So, let’s find out how to fix damaged bearings to fix the orbital sander slows down.

How To Fix Damaged Bearings?

  • Dissemble the orbital sander and check for damaged bearings
  • Clean the bearings and remove dust and dirt
  • Lubricate bearings to spin freely
  • Replace the old rusty bearings with new ones
  • Clean the orbital sander regularly
  • Keep the orbital sander in a less moisture environment

That’s how you should fix damaged bearings to prevent the orbital sander from slowing down.

Let’s see how a poor power source can cause slow spinning of the orbital sander.

4. Not Having A Good Power Source

Not having a good power source can affect the electrical orbital sander reduce its efficiency and slow it down.

Having a power source that doesn’t provide enough power to the sander can damage the orbital sander.

When lots of electrical are connected to the same power circuit or extension with the orbital sander, the extension or power circuit will get overloaded.

An overloaded power circuit doesn’t provide good current flow to the orbital sander which makes it slow down. This is caused because of the low amperage.

Plus, insufficient power can damage the internal circuits of the orbital sander as well.

When the extension cord of the power circuit is too long, that builds up high resistance resulting in poor current flow through the cord. Same as the damaged power cord.

Because of not gaining a consistent sufficient power supply from the circuit, the orbital sander fails and slows down.

Why Power Supply Cause Issues?

  • Low amperage of power supply
  • High resistance of long extension cords
  • Low-quality power circuit
  • Electrical short
  • Moisture environments

So, let’s find out how to fix the power supply to prevent the orbital sander from slowing down.

How To Fix Power Supply Issues?

  • Never overload the power circuit connecting a lot of electrical devices
  • Use a small length extension cord
  • Place power circuits or extensions in a less moisture environment
  • Use quality products
  • Replace the old power circuits with new ones

Now you know how to fix power supply issues to gain the maximum out of an electrical orbital sander.

Let’s see how a damaged motor can reduce the spinning speed of the orbital sander.

5. Damaged Motor

The sandpaper of the orbital sander moves faster when the motor works properly to provide a super smooth surface.

The damaged motor can dramatically slow down the electrical orbital sander since the motor cannot rotate freely.

The motor should be able to spin at high speed according to the supplying power.

Why Orbital Sander Motor Get Damaged?

Orbital sander motors can get damaged due to a couple of reasons. A damaged motor slows down the orbital sander and reduces the machine’s efficiency.

If you’re under warranty period better to send the orbital sander to a repair center since most of the motor issues are manufacturing problems.

Here’re the main reasons that cause the orbital sander motor not to work properly,

  • Wire burnings due to high voltage
  • Capacitor issues
  • Broken wires

So, let’s find out how to fix the motor to prevent the orbital sander from slowing down.

How To Fix Orbital Sander Motor?

  • Dissemble the orbital sander
  • Replace the motor with a new one
  • Or take the orbital sander to a service center

As you can see there’re so many fixes to solve when the issue is in the motor. So, I highly recommend you take the orbital sander for the greater good.

6. Damaged Rotor

A pneumatic sander which is also known as an air sander works on the air pressure. When the air flows into the sander, it starts to hit the blades inside.

Blades are made to move with the air pressure. When the blades start to move, the rotor will start to rotate.

When the rotor gets damaged due to various reasons, it cannot rotate freely with blades which can cause the orbital sander to slow down.

The same happens when the blades get damaged, they cannot move with the airflow. Therefore, some air will flow directly through the blades without moving them.

This causes the pneumatic orbital sander to slow down. Both blades and rotor need to rotate freely with air pressure to gain the best from the air sander.

Why Orbital Sander Rotor Get Damaged?

Orbital sander rotors can get damaged due to several reasons. Some of them are manufacturing faults that need to fix by sending them to a repair center and some can fix with simple tricks.

Here’re the main reasons for the orbital sander rotor not working properly,

  • Dust and dirt on the rotor and blades
  • Holes and cavities inside the rotor and blades due to rust
  • Keeping orbital sander in high moisture environments
  • Not cleaning the orbital sander regularly

So, let’s find out how to fix the damaged rotor to make the air sander work well with no slowing down.

How To Fix Damaged Rotor?

Follow below simple steps to identify and fix the damaged rotor of the orbital sander.

  1. Dissemble the orbital sander
  2. Clean the rotor and blades and remove dust and dirt
  3. Remove rust
  4. Replace rotor and blades with holes and cavity
  5. Apply new rotor and blades
  6. Reassemble the orbital sander carefully

That’s it. Now you know how to fix a damaged rotor to prevent the orbital sander slow down.

Let’s see how a rusted shaft can affect the speed of the orbital sander.

7. Shaft Is Rusted

The shaft has the ability to balance the rotor, blades, and bearings to spin freely with air pressure in a pneumatic sander.

When the shaft is rusted it won’t work properly and the balance between the rotor and bearings will break. This makes the orbital sander slow down.

Sometimes the whole orbital sander won’t turn on due to the failures of the shaft. So, you should take an action as soon as when the sander gets slows down occasionally due to the rusted shaft.

Why Shaft Get Rusted?

The shaft can get rusted due to many reasons. The pneumatic sander won’t well when the shaft is damaged.

Here’re the main reasons why the shaft of the orbital sander gets rusted quickly,

  • Keeping orbital sander in a moisture environment
  • Weather changes
  • Water damages
  • No proper maintenance
  • Dust and dirt build-up
  • Not cleaning the orbital sander regularly

Let’s see how to fix the rusted shaft to speed up the orbital sander again.

How To Fix Rusted Shaft?

  • Keep the orbital sander away from high humidity and moisture environments
  • Clean the orbital sander regularly by dissembling
  • Remove dust and dirt from the shaft
  • Clean the shaft using a lubricator
  • Make the shaft super smooth
  • Take the orbital sander to a service center

Following the above methods, you’ll be able to fix the orbital sander slow down due to shaft issues.

Let’s see how wrong assembling can cause the orbital sander to slow down.

8. Wrong Assembling

After dissembling the orbital sander to clean the inner components or to see some components, reassemble the part that you need to focus on carefully.

Because most people reassemble orbital sanders incorrectly without proper alignments which can result in the orbital sander slowing down.

Keeping perfect alignment is a must between components to make the orbital sander runs freely.

Why Wrong Assembling Cause Orbital Sander Slow Down?

A wrongly assembled orbital sander is so hard to fix because it is difficult to find out the exact issue of why the orbital sander slows down while working.

Here’re the main reasons why wrong assembling affects the speed of the orbital sander,

  • Missing components when assembling
  • Wrongly fitted components
  • No proper alignment between the components
  • Damaging inner parts during the assemble

Let’s see how to fix a wrongly assembled orbital sander.

How To Fix Wrongly Assembled Orbital Sander?

Make sure to assemble each of the orbital sander components correctly and carefully to prevent the sander from slowing down when working.

Otherwise better to ask for professional help since the wrong assembly can damage important parts of your orbital sander.

That’s it, folks, now you know how to fix the orbital sander and slow down the issue with all the simple fixes, and tricks.

In conclusion, let’s see some troubleshooting tips to fix any orbital sander slowing down issues with ease.

Orbital Sander Troubleshooting Tips

Follow the below chart to fix almost all the orbital sander slow-down issues to get a good knowledge about what steps you need to take when the orbital sander is slowing down.

Reason for Orbital Sander Slows DownSolution
Torn cordReplace with a new less lengthy cord
Clogged dust and dirtClean with a soft, clean cloth or use a lubricator, Replace the speed controller
Damaged bearingsLubricate bearings, Replace them with new ones, and Contact the repair center
Poor power sourceUse a separate power circuit for the orbital sander with a less lengthy extension cord
Damaged motorReplace with a new one, Contact the repair center
Damaged rotorClean dust, dirt, and rust from the rotor and blades
Rusted ShaftLubricate the shaft, Contact the repair center
Wrong assemblingContact the repair center

So, let’s answer some frequently asked questions.

Why Orbital Sander Stops When Pressure Applied?

The orbital sander stops when pressure is applied when the brushes are clogged with dust and rust, or when the power cable is damaged.

You can fix orbital sander stops when applied pressure by cleaning the brushes to remove dust and rust, lubricate bearings and replace clogged brushes with new ones.

Use small-length power cables to avoid high-pressure build-up which can cause the orbital sander stops when the pressure is applied.

Clean the orbital sander regularly and keep it in a less moisture environment to prevent dust and rust building which can reduce the machine’s efficiency.

What Happens If You Apply Too Much Pressure On A Sander?

Applying too much pressure on the sander can damage the internal components of the sander and may damage the surface.

High pressure slows down the sander and reduces its efficiency. Plus, it can get too hot pretty quickly. Let the sander do the job with light pressure.

Disk sander can break or damage due to the high pressure and you need to handle the sander firmly without applying much pressure on it.

How Do You Lubricate An Orbital Sander?

You can lubricate the orbital sander to remove rust, dirt, and dust and keep the machine clean which helps to prevent the orbital sander from slowing down.

Lubrication is only used for pneumatic orbital sanders (air sanders). Electric sanders are not required to lubricate.

Here’s the procedure for lubricating an orbital sander,

  1. Add 1 – 2 drops of lubricating oil into the air inlet of the pneumatic sander
  2. Keep the machine run for 30 seconds to let the excess oil drained
  3. Add 2 drops of lubricating oil per day for a machine that starts frequently

Make sure not to over-lubricate the orbital sander since oil may start to drip from the muffler.

If the filter is saturated with lubricating oil, you should replace the muffler immediately.

Better to use the FRL unit which is known as Filter, Regulator, and Lubricator to lubricate the oil sander properly with no issues.

What Speed Should I Run My Orbital Sander?

The orbital sander should run speed at about 1 inch per second which means 12 inches per linear foot. Usually, orbital sanders run slowly, and random oscillations will do the job perfectly at slower speeds.

Orbital sanders do the oscillations speed at 12,000 oscitations per minute which is quite an impressive value. But this can vary upon the variable speed orbital sanders.

Moving the orbital sander slowly on the surface helps to reduce swirl patterns and is useful to get an even nice and smooth finish with ease.

Why is My Sander So Slow?

Your sander is so slow when the brushes are dirty or rusty, torn cords, rusty bearings, extremely high pressure, and lack of lubrication.

Clean the orbital sander regularly and use with light pressure and move it slowly to make the sander speed.

Maintain the air pressure at 90 PSI to work the sander ideally.

Plus, make sure to keep the backup pads well-maintained and fresh for better use of the orbital sander with no slowing down.

What Is The Best Way To Speed Up The Sanding Process?

The best way to speed up the sanding process of the orbital sander is to clean the brushes and bearings to remove dust, dirt, and rust and replace the old components with new ones with a proper power supply.

Maintain the orbital sander well and store it in a dry less moisture environment to avoid water damage and keep the rotor, motor, and blades clean with no slowing down.

Did I cover all you wanted to know about Orbital Sander Slows Down

In this article, we have deeply discussed about what are the reasons the orbital sander slows down and we discussed each of the reasons with all the simple fixes that can use by any woodworker with ease.

If your orbital sander is still under warranty period and you have no idea how to dissemble the orbital sander to fix certain slowing down issues, better to contact the repair center without taking risks.

The orbital sander slows down due to clogged dust and rust, torn cords, poor power source, damaged rotor and motor, rusted shaft, damaged bearings, and wrong assembling. Most of the orbital sander slowing down issues can fix by cleaning and removing dust, dirt, and rust using lubrication.

Furthermore, I’ve answered frequently asked questions as well.

Hope you have gained good knowledge about fixing the orbital sander slows down the issues.

Try to fix orbital sanders that slow down by yourself if the issue is a little one. For bigger ones, better call for professionals.

Troubleshooting makes you a pro at working with sanders!

Walter Parker is a woodworking enthusiast. He is passionate about woodworking projects & plays with woodworking tools having spent over 2 decades as a leader for Woodworking Planet. He wants to make people love woodworking! Read More About Him!

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