A potentiometer is an electrical component that helps control the flow of electricity. They are often found in devices such as stereos, radios, and other electronics. If your potentiometer isn’t working correctly, it may need to be cleaned. In this article, we will discuss how to clean a potentiometer using common household items. We will also provide some tips on how to prevent dirt and dust from building up on the potentiometer in the future.
What is a Potentiometer?
A potentiometer is a simple electrical device that allows you to control the flow of electricity in a circuit. It consists of a resistor and three terminals. The amount of resistance between the terminals can be adjusted by turning the knob or moving the slider on the potentiometer. This makes it useful for controlling things like the volume of an audio signal or the brightness of a light.
Potentiometers are often used in electronic devices such as radios and TVs. They can also be found in some musical instruments, such as electric guitars. [1]
Types of Potentiometers
There are two main types of potentiometers: rotary and linear/slide.
Rotary potentiometers
Rotary potentiometers, also known as “knobs”, are the most common type of potentiometer. They consist of a shaft that can be turned to adjust the resistance. The resistance is usually adjusted by turning the knob clockwise or counterclockwise.
Slide potentiometers
Slide potentiometers, also known as “faders”, are similar to rotary potentiometers, but they have a linear slider instead of a shaft. This allows them to be used for things like mixing audio signals or controlling the volume of an amplifier. [1]
In the world of potentiometers, there’s a dynamic duo: rotary and slide. Rotary, the classic “knob,” employs a turning shaft to tweak resistance, while slide, aka “faders,” rocks a linear slider. Knobs are the go-to for general adjustments, while faders shine in tasks like audio mixing or amplifier volume control. Each has its niche in the symphony of electronics.
David Hall, Power Electronics Engineer, Houston
Why Should You Clean a Potentiometer
When dirt and dust build up on the contacts inside a potentiometer, it can cause problems with the electrical connection. This can result in crackling noises, static interference, or even complete failure of the device. If you have ever turned the volume knob on your stereo and heard a loud, static-y noise, then you know what we’re talking about. Additionally, a build-up of dirt and dust on the potentiometer’s knob can make it difficult to turn.
The replacement of potentiometers is costly, so it is important to clean them regularly to avoid these issues altogether. [2]
Cleaning a Potentiometer With Deoxit Contact Cleaner
The first method of cleaning we will explain is using a contact cleaner. This is a specialized type of cleaning solution that is designed to remove dirt, dust, and other contaminants from electrical contacts.
Test the potentiometer before cleaning it
The first step is to test the potentiometer to see if it is actually dirty. This can be done by using an oscilloscope to measure the resistance of the potentiometer while it is being turned. If the resistance readings are jumpy or erratic, then the potentiometer is probably dirty and will benefit from being cleaned.
Gather the Supplies Needed
Once you decide that cleaning the potentiometer is the best course of action, you will need to gather the supplies needed to do the job.
You will need:
Deoxit contact cleaner
This is a specialized cleaning solution that can be purchased at most electronics stores. Make sure to get the correct type of cleaner for your potentiometer.
Safety goggles and gloves
Due to the chemicals involved, it is important to wear safety goggles and gloves when using contact cleaner.
Cloth
Additionally, you will need a lint-free cloth or other soft material to wipe away the dirt and dust.
Once you have all of the supplies gathered, you are ready to begin cleaning the potentiometer.
Gain access to the potentiometer
To proceed further, you will need to disassemble the device so that you can access the potentiometer. In some cases, this may be as simple as removing a few screws.
Spray the cleaner on the potentiometer
Start by spraying a small amount of contact cleaner onto the cloth. Then, wipe down the potentiometer’s shaft and knob with the dampened cloth. Be sure to avoid getting any cleaner on the electrical terminals or other sensitive parts of the device.
Wiggle the knob
After you have wiped down the potentiometer, you will need to wiggle the knob and shaft back and forth. This helps to loosen any dirt or debris that may be stuck in the mechanism.
Repeat this several times
If the potentiometer is still not working properly, you can try spraying a small amount of contact cleaner on it again and repeat the process.
Let it dry before reassembling
Once you are satisfied with the results, allow the potentiometer to dry for a few hours. Since you are working with electronic devices, it is important to make sure that all of the cleaner has evaporated before turning the device on again.
Once you have finished cleaning the potentiometer, you can reassemble the device and test it to see if it is working properly. In most cases, the potentiometer will be as good as new after being cleaned. However, if the problem persists, you may need to replace the device.
A crucial factor to keep in mind is to avoid using any type of conductive lubricants as these can actually do more harm than good. If you must use a lubricant, make sure it is compatible with plastic or rubber. [2], [3], [4], [5]
Cleaning With Isopropyl Alcohol
If contact cleaner is not available, you can also use isopropyl alcohol to clean the potentiometer.
The process works in the same way, spray a little bit of isopropyl on the pot (or fader) and turn/move it back and forth a few times. Be sure not to use too much isopropyl alcohol, as it can damage the plastic housing of the potentiometer. Then, use a paper towel or lint-free cloth to wipe off the remaining alcohol on the surface.
Repeat this process a few times until the knob or wiper are moving smoothly. Once you’re satisfied with the results, replace the pot back into its housing and screw it in place. [2]
Cleaning With Compressed Air
This method is not as effective as the other two but can be useful for regular maintenance. Direct a stream of compressed air around the potentiometer to blow any dust or debris out of it.
You can use a can of compressed air or an air compressor. If you’re using a can of compressed air, be sure to hold it upright so that the propellant doesn’t freeze and damage the potentiometer. You may need to do this a few times to get all of the dirt off. [2]
Disassembly and Manual Cleaning
If the above methods didn’t work, the last option is manual clean.
The first step is to disassemble the potentiometer. This will give you access to all of the nooks and crannies where dirt and grime can accumulate. Once you have access to the internals of the potentiometer, use a soft brush (like an old toothbrush) to gently remove any loose debris.
For tougher deposits, you may need to resort to manual cleaning with a cotton swab or Q-tip. Dip the swab in isopropyl alcohol (rubbing alcohol) and use it to scrub away stubborn dirt and grime. Additionally, you also can soak the components in the isopropyl alcohol.
Be careful not to use too much force, as you don’t want to damage the delicate internals of the potentiometer.
Once you’ve removed all the dirt and grime, let the components dry and reassemble the potentiometer and test it out. [2], [4]
Christopher King, PCB Manufacturing Technician, San Jose
FAQ
How do you fix a scratchy potentiometer?
The most common cause of a scratchy potentiometer is dust and dirt build-up on the contact points. To clean the contact points, you will need to apply a contact cleaner.
Once you have applied the contact cleaner, turn the potentiometer back and forth several times to work the cleaner into the contact points. After a few minutes, you should notice an improvement in performance. If the problem persists, you may need to replace the potentiometer.
How do you clean a sealed potentiometer?
Sealed potentiometers don’t require cleaning like non-sealed types do. Because they are sealed, they don’t suffer from the same exposure to dust, dirt, and other contaminants. However, if your sealed potentiometer starts producing a scratchy sound, you might want to look into replacing it.
How do you recondition a potentiometer?
The most important thing to remember when reconditioning a potentiometer is to avoid using any cleaning solutions that could damage the unit. The best way to clean the contacts is by gently scrubbing them with a soft, dry cloth or a cotton swab. If the potentiometer is extremely dirty, you can use compressed air to remove any debris before scrubbing the contacts.
Once you’ve cleaned the contacts, it’s important to lubricate them to prevent future corrosion. You can use a variety of lubricants, but make sure to avoid anything that could potentially damage the plastic components of the potentiometer.
Useful Video: How to Clean & Resurrect an Embalmed Potentiometer (With Bonus Rant)
Conclusion
So, if you’re experiencing noise or sound quality issues with your potentiometer-based pedal, it may be time for a good cleaning. You have a few different options for how to go about this – spray it down with some contact cleaner, use isopropyl alcohol on a cloth, or blast it with compressed air. If those don’t do the trick and you need to take things apart for a manual clean, just make sure you put everything back together correctly when you’re done!
References:
- https://www.electrical4u.com/potentiometer/
- https://www.keithrobertmurray.com/articles/potentiometer-cleaning-showdown.html
- https://sps-support.honeywell.com/s/article/I-have-an-audio-potentiometer-that-is-scratchy-and-needs-cleaning-How-do-you-recommend-I-do-this
- https://support.newgatesimms.com/potentiometer-maintenance-and-lubrication-case-study/
- https://support.newgatesimms.com/lubricants-and-possible-plastic-or-rubber-compatibility-issues/