The role of the commutator is an essential part of any motor that requires the use of carbon brushes. It is used to create a proper seal around the brushes, while also pre-forming the brushes and cleaning commutator surfaces.
It is important to seal correctly with the correct paper, otherwise the carbon brushes inside the motor will increase friction, causing them to wear faster than normal. It can also cause undue damage to the commutator itself, leading to motor failure, costly maintenance, and a lot of unnecessary motor downtime. Properly sealed carbon brushes also allow almost immediate use of rated current.
How commutator paper works
When you create a seal for your carbon brushes, you should start by choosing a commutator paper that is the proper width for the motor you are using. It should be wide enough to reach all of the carbon brushes in the commutator. Always install paper with the frayed side out. Duct tape can be used to attach the paper to the switch. Just make sure you keep walking around the switch. You should then turn the commutator by hand in one direction until the brushes cover approximately 75% of the radius.
Choosing the Right Switch Paper
Some people may use emery cloth as a cheap way to avoid buying paper, but that's not a good idea at all. One of the brands that engineers trust the most is Garnet. This particular type of paper has been around for a long time and is trusted by many engineers around the world.
In addition to the brand, you should also be concerned with the grain size of the paper before you buy it. The grain you need depends almost entirely on your use. For example, one of the most commonly used types of paper is 80-grit sandpaper, which helps with the main shape of the brush. On the other hand, once these brushes are in place, you will need another type of paper. Another common type of commutator paper is 220-grit sandpaper, which is often used after 80-grit sandpaper to help create a fine finish.
Installing the Carbon Brushes
It is also important when working on the carbon brush seals to make sure they are properly seated. Buying the right commutator paper is the first step. Then you also need to make sure that all carbon brushes are properly seated. When it's time to replace them, be sure to replace all the brushes at the same time. If your motors are running properly, they should wear evenly anyway.
The carbon brushes you choose should have a pre-cut radius so you know they will fit correctly. Remember to vacuum up any excess toner each time you change the brushes so it doesn't fall into the motor and cause additional wear and tear on the motor.
Certainly not worth taking shortcuts, especially when it comes to engines. The commutator and the carbon brushes located on it form one of the most important parts of the motor. You just can't afford cheap parts.
