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Dual-Action polishers and Orbital buffers
The motors and drive units on these two types of polisher's oscillate in an eccentric circular motion. This type of motion is much safer to the paint because it's virtually impossible to apply too much concentrated pressure in one place at one time. Chances are good that when too much pressure is applied, the oscillating action will come to a stop thereby protecting the finish.
Because these types of machines oscillate instead of rotate, they will not instill the dreaded buffer swirls or holograms into your finish as long as you use the appropriate chemicals, buffing pads and bonnets. This safety feature makes these machines highly popular with enthusiasts who would like to use a machine but at the same time, are afraid of burning or inflicting swirls into their car's finish.They are versatile – can be used for cleaning, polishing, and applying waxes.They push polishing oils and protective waxes into the pores and microscopic surface imperfections far better than your hands can ever accomplish.
Rotary buffers
Rotary buffers are drastically different in the way they work compared to Dual-action polishers and Orbital buffers.The drive unit used in a rotary buffer is referred to as a direct drive. What this means is the auger, (the threaded part to which the backing plate attaches), is driven directly off the electric motor. This results in a powerful rotating motion. This rotating motion is typically clockwise as you look at the rotary buffer from behind, as though you were using it on a panel. Because the rotary buffer is a direct drive machine, it can do a lot of work very quickly. By work, we mean, the rotary buffer will remove paint.Sometimes removing paint is necessary in order to create a high gloss, defect-free finish. Example: If you have a scratch in your car's finish, say someone keyed your car, or a cat jumped up on the hood and left behind claw scratches. In order to remove these scratches, you will need to remove enough paint surrounding the scratches in order to make the surface level.
Second Example: Many cars, after being painted, are wet-sanded in order to remove orange peel or to bring the surface to a show car quality finish. After the finish has been sanded, the way you remove the sanding marks is to buff the finish with a cutting compound and a rotary buffer. The cutting compound abrades the paint, removing, or leveling the finish until it’s completely flat.
After the surface is buffed flat, it will then be polished with a cleaner/polish on the rotary buffer to restore a swirl-free, high gloss finish. Rotary buffers are necessary to do both of these procedures because both of these procedures require that some portion of the paint is removed.Dual-action polishers and Orbital buffers do not have an aggressive enough action to remove small particles of paint in an effort to remove most defects, including sanding marks. This is the same reason Dual-action polishers and Orbital buffers are safe… they don’t have an aggressive action, thus they are safe. However, because they are safe (do not have an aggressive action), they are not aggressive enough to remove all but the finest of scratches.
Do not purchase a dual action polisher or orbital buffer hoping to use these to remove major or even minor scratches, as they are just not aggressive enough. They can often be used to remove fine or shallow scratches and swirls, but they will not remove any scratch that is deep enough to place your fingernail into.Remember, using a rotary buffer successfully requires both skill and experience. If you use a rotary buffer and are not skilled in its use, you can easily apply too much pressure to the paint and burn right through it, requiring a new paint job.