Commutator paper is an important 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-shaping the brushes and also cleaning the surfaces of the commutator.
Having a proper seal with the right paper is important because if you don't, the carbon brushes inside the motor will have increased friction, which will cause them to wear down much more quickly than they normally would. This can also cause excessive damage to the commutator itself, which will result in a breakdown of the motor, expensive maintenance, and a lot of unnecessary downtime for the motor. Sealing the carbon brushes in properly also makes it possible to use rated current almost right away.
How Commutator Paper Works
When you're creating a seal for carbon brushes, you should start by selecting commutator paper that is the appropriate width for the motor you are working on. It should be just wide enough to be in contact with all of the carbon brushes that are riding on that commutator. When installing the paper, always make sure that the abrasive side is out. Masking tape will make it possible to attach the paper to the commutator. Just be sure that you go all the way around the commutator. Next you should use your hand to rotate the commutator in the direction it goes until about 75 percent of the radius is covered by the brushes.
Selecting the Right Kind of Commutator Paper
Some people may use emery cloth as a cheap way to get around having to purchase paper, but it simply isn't a good idea. One of the brands that is most trusted by engineers is Garnet. This particular type of paper has been around for a long time and is trusted by many engineers all over the world.
In addition to the brand name, you also have to be concerned about what grit the paper is before you purchase it. The grit you need depends almost entirely on the use of it. For example, one of the most common types of paper used is 80 grit paper, which helps with the main shaping of the brushes. On the other hand, once those brushes are shaped, you will need a different kind of paper. The other common type of commutator paper is 220 grit, which is often used after the 80 grit to help create a fine finish.
Seating the Carbon Brushes
It is also important when you work on the seal for those carbon brushes that you make sure they are seated correctly. Buying the right kind of commutator paper is the first step. Then you should also make sure that all of the carbon brushes are seated appropriately. When it is time to change them, be sure to change all of the brushes at the same time. If your motor is running correctly, they should wear evenly anyway.
The carbon brushes you select should have a precut radius so that you know they will fit correctly. Whenever you change the brushes, remember to vacuum up the extra carbon dust so that it does not fall down into the motor and cause problems and extra wear and tear on the motor.
It certainly never pays to take shortcuts, especially when you are dealing with questions about motors. The commutators and the carbon brushes that sit inside of them form one of the most important components of the motor. You simply can't afford to have cheap parts.