Car cleaning power tools are made up of various components, like switches and carbon brush caps that come together to create an intricate yet powerful system that helps you achieve a professional-grade clean. However, the complexity of these tools can sometimes cause issues due to the wear and tear of mechanisms over time, with the most common issue being the deterioration of carbon brushes. Carbon brushes may be small, but they play a vital role in cleaning tools.
If you’re interested in learning more about maintaining your car polishers and vacuuming tools to ensure longer life and efficiency, we’re here to help. Keep reading as we delve into what a carbon brush is, how it works and how to detect whether it needs replacing, so you can ensure efficient use of your car cleaning equipment.
What are carbon brushes?
Carbon brushes are small, rectangular components made from carbon and other composite materials that are found inside power tools, serving as a connection point between the stationary and rotating parts of a tool. Carbon brushes facilitate the transfer of electric current to the motor's rotor or generator's armature. They are used in car cleaning tools such as rotating polishers and electric cleaning brushes by managing significant amounts of energy, however, they will wear over time and need replacing to ensure your tools continue to work properly.
Why do carbon brushes wear out?
Carbon brushes are designed to naturally wear out over time. The reason they wear out is primarily due to friction, electrical load, and other environmental factors they may encounter during operation. Given the multitude of working parts inside of power tools, carbon brush issues are bound to arise and it’s crucial to be able to find the root of the problem. Below we have listed a few of the key reasons carbon brushes may wear down so you can prevent performance issues and maintain equipment quality for as long as possible.
Continuous friction
As carbon brushes have constant contact against the rotating parts in the machine to maintain electrical contact, this can create a continuous friction that over time, will gradually wear away the carbon material. If the machinery has fast rotation speeds, this may increase friction leading to faster wear of the carbon brushes.
Poor fit or misalignment
It’s also important to note that if the carbon brushes are not well-fitted to the commutator, this uneven contact can cause faster deterioration. Any misalignment due to improper installation or wrong materials can lead to uneven contact, causing one side of the brush to wear faster than the other. This may be a possibility if your brush is made from softer composite materials, rather than those made with harder or reinformed carbon composites, therefore when replacing your carbon brushes it's important to keep the material in mind.
Electrical arcs
Carbon brushes can also be damaged due to small electrical arches that may form at contact points between the brush and commutators during operation. These arches will generate heat and erode the carbon material, and this is most common with high electrical loads or voltage fluctuations, as the uneven current flow can increase arching and accelerate brush wear. This may also come as a result of the condition of the commutator surface, if it is worn, rough or not perfectly circular, it may cause irregular brush contact and lead to grinding down brushes quickly.
Excess use and unfit operating conditions
To prevent excessive wear, we recommend keeping your operating environment free from any potential contaminants and avoiding overuse of your tool. Any dust or debris can assimilate on commutators or slip rings, causing accelerated wear. Extreme temperatures or high humidity levels can also put your carbon brushes at risk of wear as oxidation or corrosion may occur on the commutator, causing increased friction. In addition to this, prolonged use of any tool without breaks can cause carbon brushes to overheat, again leading to rapid deterioration.
Poor maintenance is also a key factor in carbon brush wear. Regularly cleaning and inspecting brushes and commutators is necessary to ensure the optimum operation of your tool.
How do I know if my carbon brushes are worn?
Recognising when your carbon brushes are worn can be tricky, however, by detecting early signs of wear you can prevent potential damage to your tool by replacing them as soon as possible. Below we have listed a number of signs to look out for that will determine whether your carbon brushes are worn and need replacing.
Reduced performance
An initial indicator that your carbon brush may need replacing is seeing a decline in the tool's performance. If carbon brushes are wearing out, the tool may cut out during use, or make unusual noises during operation, signalling decreased motor efficiency due to wear.
Burning smell
Another indicator that your carbon brush is worn down is an unpleasant odour associated with burning. If you encounter this smell, you must immediately stop using the tool and consult a professional repairer for a diagnosis as there may also be other issues such as arching.
Sparking or arching
While slight sparking may be normal depending on the tool you are using, frequent large sparks may indicate that there is poor brush-to-commutator contact and excessive wear. This can be a result of a damaged commutator, incorrectly installed brushes or a shortening of brush below its recommended length which can cause increased sparking at the contact point.
How to check if carbon brushes need replacing
To ensure the optimum performance of your equipment, we suggest checking your carbon brush frequently to proactively maintain your tools. To be on the safe side, don’t just wait until you notice signs of wear, although daily maintenance may not be necessary, periodic inspections of carbon brushes can help to ensure they remain in peak condition.
To access the carbon brush safely, always read the motor manual of your tool first to see if it instructs you on how to check the carbon brush before attempting it yourself. Make sure your tool is not plugged into any electricity before opening it up. To know what to look for, a typical carbon brush is a solid block of material that has a flexible braided wire or spring attached to it for connection, however, the size, shape, and material will depend on the machine's design and operating requirements. The carbon brush will be located in the motor housing. To allow for better access, remove the motor from the tool to give yourself more room to work, then, unscrew the carbon brush cap.
Once you can see your carbon brush, look for any obvious signs of wear including breakage, crumbling or a change in spring colour - if you can see minimal or no carbon remaining, you should replace the brush. If the brush appears to be worn down to any less than a quarter of an inch, it will need to be replaced. Some brushes may have an auto-cut feature which signals a need for a new brush, you will be able to recognise this as a small pin popping out of the brush.
How to minimise carbon brush wear
Specific components of most tools will need to be replaced at some point throughout their lifetime due to general wear and tear, however, there are ways to help minimise carbon brush wear to prolong the life of your tool.
The best way to reduce wear on this vital component is to regularly inspect the carbon brush and clean surrounding commutators to ensure proper operation. You should also avoid overloading the motor or running it for prolonged periods of time without breaks.
As for fixing carbon brushes, once they're worn or damaged, they can't be repaired but they can be replaced which is a relatively straightforward process. Ensure that when replacing you choose high-quality brushes that are the right size and are appropriate for the specific application and load requirements. Make sure when installing that you check the alignment and ensure proper spring tension to maintain consistent contact with the commutator.
Maintain your car detailing equipment with My Car Cleaning
To streamline your car cleaning process and ensure you get the perfect detailing service every time, keeping your tools in optimal condition is essential. Browse through our full collection of machine-polishing brushes to find the right fit to replace your carbon brush.