how to use a car polisher

How to Polish a Car Using Dual Action Polisher

Everyone loves having a wet-look shine on their car. Too bad, then, that what was once possible by hand is no practical. Cars built in the 1980 and earlier have much softer paint than a car built today, and paint system is getting even harder.

The means the only practical way to polish a newer car is with an electric car polisher, like the Porter Cable 7424XP seen below. Please continue reading and you will discover why this polisher — and other dual-action car polishers — are the safe, effective solution for all car owners.

Most cars built since 1990 have a clear coat finish. What this means is that a color coat is applied over a primer, followed by a coat of clear paint. The purpose of the clear coat is to give the paint its high gloss, vivid color, and appearance of depth.

The clear coat layer also protects the color. Plus, because the clear coat protects the color, the paint manufacturers continue to engineers new technologies that make the clear coat even harder for a finish that will last as long as possible. That’s why an electric car polisher is now a necessity, not a luxury.

Porter Cable 7424XP Package Offer

The purpose of “How to Polish a Car” is to show you the proper use of a dual-action car polisher, like the Porter Cable 7424XP, the Meguiar’s G110v2 polisher, or the Griot’s Garage Random Orbit polisher, to properly polish and buff your car.

If you don’t have a car polisher, the link above, which takes you to Tools-Plus, is the best deal around. You will also find the Porter Cable 7424XP at Home Depot, Loews, and Sears, but you will have to pay local sales tax, and they do not provide a flexible Velcro backing plate. Trust me, I have searched high and low and have not found a better deal than the Tools-Plus 7424xp package with free shipping.

Yes, but will it Remove My Swirls, Water Spots, Scratches, Oxidation, etc?

If you reached this site searching for a solution for paint imperfections, such as swirl marks, water spot etching, dullness from oxidation, scratches, and so on. If so, you’re in the right place, because a dual-action polisher is a correct solution for all minor surface-level paint correction problems.

Said another way, if the damage to your paint is in the top layer of the clear coat itself (not into the color coat or the primer), then you can buff your car’s problem away with a dual-action polisher. If the damage to your car’s paint is deeper than the thickness of a sheet of paper, then a dual-action polisher will make it look better, but it won’t obliterate it.

Introduction to Dual Action Car Polishers

A dual-action car polisher also called a DA polisher”, operates by orbiting, not spinning, the polishing pad. The pad itself is free to spin or stop spinning; it’s just along for the ride.

The polishing action on a dual-action car polisher often called a random orbit or orbital polisher is designed to prevent holograms, paint burns and other types of paint damage. Paint holograms are those symmetrical buffing marks, or swirls, that are put into the paint when someone buffs a car with a high-speed buffer without knowing what they are doing. That’s one of the real benefits of a DA polisher; very little skill or experience is needed.

If you use a dual-action car polisher with the appropriate care, the dual-action rotor mechanism completely eliminates the possibility of damaged paint. DA car polishers are completely safe for all types of paint and clear coat finishes. So, unless you use the polisher to beat your car to a pulp, it won’t damage your car’s paint!

Dual-Action Car Polisher Buffer Benefits

The most important benefit of a dual-action car polisher is that it closely simulates how you would pamper your car’s paint polishing by hand. The big difference is that the electric car polisher buffer can make up to 6,800 circles every minute. Have you ever tried doing that by hand!

The reason the dual-action car polisher is so effective, yet gentle like a lamb.Because the foam polishing pad can rotate freely on it’s own bearing while the rotor whirls it around. As you run the tool, the pad rotate as it orbits. The pad rotation is centrifugal force in action, not forced drive. This “dual-action” of orbiting and spinning is how “DA” car polisher got their nickname.

If you currently have or have previously owned an “orbital car polisher” that make a bunch of noses, but does little or nothing for your car’s paint, you will admire the 7424XP as the quality tool it is. Most consumer car polishers simply don’t have the required power to get the job done, and the large pad design does not allow effective transfer of energy to the pad and polish. Porter Cable’s 7424 was the first car polisher buffer to break through the limitations. That’s why it became the defacto industry standard.

The rotation of the foam polishing pad by centrifugal force is beneficial to the outcome of your paint polishing work. While working, you will always be striking a delicate balance between downforce required to work the polish and pad rotation necessary to get the finish to run clear and buff out.


Before actually going into the operation of these machines, let’s first discuss safety features.


The Porter Cable 7424XP polisher has a reversible side handle. The side handle makes the machine easy to hold and control, even when working on vertical surfaces.

Using the side handle is a personal choice. It offers a measure of safety, sure enough, but if you have large hands, you can grip the polisher by the head end with one hand and the rear with the other. This is how I use the polisher, and it’s comfortable. I find the handle just gets in the way.

The Meguiar’s and Griot’s Garage polishers have a “D” handle design. The D handle allows you to grip the polisher on-center. Some people feel this makes polishing easier and stops the polisher from wandering and wobbling.

Speed Control

The Porter Cable 7424XP functions at 2,500 to 6,800 operations per minutes (OPM). The Meguiar’s G110v2 has a slightly larger speed range, slowing all the way down to 1800 OPM.

To control the speed, you rotate a thumbwheel speed dial. The speed dial is on the top-rear of the Porter Cable 7424XP, and on the rear of the original 7424 polishers (Meguiar’s and Griot’s Garage polisher are also on the rear).

The OPM measurement is used instead of revolutions per minute (RPM) to distinguish the difference between orbits and center shaft revolutions. At 6,800 OPM, this machine is really moving!

NOTE: You can adjust polisher speed with the polisher running, but don’t lift the polisher from the surface of your car to do so. If you do, you will have an amazing mess to clean up, as a polish with be thrown in about a 12′ radius. You will only make this mistake once!

Good Safety Comes First

Warning: Failure to follow safety these basic safety precautions may result in bodily harm or damage to your vehicle.

Wear safety glasses when operating this tool to avoid eye injury from flying debris.
Always switch the machine off and unplug the machine from the power source before changing accessories. Switching on the machine while changing accessories may cause an injury.
Never operate the car buffer/polisher unless the polishing pad is pressed against the surface to be polished or buffed. This means that you both start and stop the machine while the tool it is resting flat on the surface of the car.


It’s possible to use a range of Velcro backing plates and pads with the Porter Cable 7424XP and other dual-action car polishers. Velcro backing plates are available in sizes ranging from 3 to 6 inches.

The Porter Cable 7424XP car polisher does not come with a Velcro backing plate. Many sellers bundle this necessary component with the polisher. Both the Meguiar’s and Griot’s Garage polishers come standard with the proper size Velcro backing plate for use with foam pads ranging in size from 5.5″ to 7.5″.

The effective pad contact diameter for the Porter Cable Polisher is 4 to 7 inches. To achieve the desired results, polishing pads must be paired with an appropriate car polish. In other words, do not use a fine hand polish with a cutting pad and expect it to remove heavy oxidation or swirl marks. It simply won’t work.

For most purposes, you can get away with three grades of foam polish pads:

  • Light Cutting — For removal of oxidation, fine scratches, swirl marks and other minor paint defects.
  • Polishing — For normal light polishing and paint cleaning.
  • Finishing — For high gloss polishing and applying liquid waxes.

We discourage the use of course “cutting” pads by inexperienced users due to the real potential of removing too much paint material or creating severe hazing in the paint.

Protect by Masking

If you’re not careful, polishing can damage trim. When you need to polish close to a car’s trim, we recommend masking it with painter’s masking tape.

Here’s why. If you run your polisher over black plastic trim, rubber seals or brushed aluminum trim, you will change the original matte finish. For example, flat or satin finishes will become glossy.

Masking around window trim, door handles, windshield washer nozzles, antenna masts, door guards and other trim will not only prevent damage but will also reduce your clean up. Be safe; take the time to mask off your trim.

Use Polish Sparingly

Many people mistakenly believe that polish should be used liberally. Before the latest generation of water-based polishes, this was true.

Use modern polishes sparingly. Usually, 4-5 pea size dabs at a time is enough. If you’re working a 2′ by 2′ area and your polish takes longer than 2 minutes to buff out clear, then you’re using too much polish.

Practice Safe Polishing

Tilting your Porter Cable 7424 will quickly destroy foam pads (it causes the backing plate to cut into the pad) and may build-up enough heat with a rubbing compound and cutting pad to burn the paint.

Keep Your Pad Clean

I like to prime a fresh, clean pad with a shot or two of detailing spray. Doing so makes the initial buffing a little smoother and helps distribute the polish. Use just a light mist. Don’t drench the pad.

If your pad becomes saturated with polish, there’s not much you can do except clean it and let it dry. Switch to a clean, dry pad and use less polish.


The Porter Cable, Meguiar’s and Griot’s Garage polishers are low maintenance tools. However, the polishers do require periodic lubrication.

The head-end of the tool is a transmission that contains gears and bearings. The transmission case is packed with red lithium grease. If you use your polisher frequently, the grease should be replaced yearly. For the typical enthusiast, sending the machine in for lubrication every two or three years should be sufficient. If you feel comfortable doing the job yourself, all you need is a can of red lithium grease and a screwdriver.