There are two kinds of buffers that people here use. The first kind is an orbital, the second is a rotary. I've copied and pasted some info I posted on another board which explains both a bit more. Hope this helps.
Bill.
---------------------------------------------------------------------------------
Q: I heard that using machines to polish isn’t safe. Someone told me that I could burn a hole in my paint. Is this true?
A: It depends on the machine. Rotaries can definitely burn a hole in paint even when used by an experienced professional. A random orbital polisher like the PC is completely safe even for a total beginner.
Q: What is the difference between a rotary and an orbital? Why is one safe and the other isn’t?
A: Rotaries spin in a consistent circle. If you leave it on the same spot for too long then the heat generated by the consistent motion can burn a hole in your paint. Conversely, an orbital does not spin in a consistent circle, but rather a random spinning motion. This randomness makes the polisher safe (regardless of how long it is left in the same spot) because it does not generate anywhere near the same amount of heat as a rotary.
Q: If heat is so bad, why do people use rotaries?
A: It's not that the heat is bad. The heat is necessary to break down the abrasives in many polishes, as well as break down the paint to the point where deep surface imperfections can be removed. Heat is a necessary ingredient for adresing serious paint imperfections.
Q: How is the PC so much better than my hand if it does not generate a lot of heat?
A: True, the PC may be safe and produce minimal heat. But it does have the ability to produce more even and uniform results that are not achievable by hand. The PC may not produce the heat of a rotary, but it still does an excellent job of breaking down the abrasives in medium to fine polishes. Your hand will have a hard time breaking down any abrasive in any polish.
Q: I already have a craftsman (or other brand that’s not a PC) orbital. Is this ok to use instead?
A: No. Most other orbitals are one speed (the PC is six) and their motors bog down as soon as they touch your paint rendering them useless. The biggest advantages of the PC are it’s variable speeds and strong motor.