The Porter Cable 7424 dual-action car polisher started the pro-consumer car polisher market life more than a decade ago.  The machine started as a sander for woodworkers.  Much like custom car builders, fine furniture artisans sculpt a piece of furniture, stain it to a desired color, then spray it with multiple coats of clear polyurethane. To achieve the final finish, they wet sand, compound, polish and wax.

Today there are more dual-action polisher options, including the Ultimate Detailing Machine Model 1000 and the Meguiar's G110 polisher.  To the consumer's benefit, all of these polisher use the same attachments and operate in the same manner.  In so far as a standard exists, the Porter Cable 7424 is the industry standard dual-action car polisher.

The basics of any polisher system are the polisher, a Velcro backing plate, foam polishing pad and polish.

With the introduction of foam polishing pads into the paint and body industry in the 1970's, it’s not hard to see how the Porter Cable 7424 came into use on car finishes.  Since the late 1990's, the Porter Cable 7424 polisher has gained recognition as one of the most effective and safest polishers for car enthusiasts and car detailers alike. Why did the Porter Cable 7424 car polisher become so popular within the car enthusiast hobby?  Let’s explore the inner workings of a dual-action car polisher and find out.

Industry standard dual-action car polishers use an offset spindle that freely orbits around the center shaft.  A counterbalance weight dampens vibrations.

A dual-action car polisher (often called "random orbit" or "orbital") is a machine that operates by orbiting the polishing pad around a center spindle while the pad freely spins on its own axis. A counterweight on the opposite side of the center spindle dampens vibration for smooth operation. The tool head action, often called orbital, prevents the creation of holograms (symmetrical buffing marks), paint burns and other forms of paint damage often associated with high-speed buffing machines. When used with proper care, the Ultimate Detailing Machine’s design virtually eliminates the possibility of paint damage.

The orbiting head action, combined with a high-speed motor offers the same gentle polishing action as your hand, only at super high speed.

The polishing action of a dual-action polisher closely mimics that of circular hand polishing. Imagine being able to make 2,500 to 6,000 tight hand circles in a single minute and you’ll have a pretty good idea of how the Ultimate Detailing Machine does its job. It works just like your hand, only at super-human speed! Some people have defined a dual-action polisher's tool action as “jiggling”, but this is not the case. The head freely rotates on a bearing and orbits around the centerline driveshaft. Rotation is a free-wheeling action of the backing plate spindle caused by the orbiting head. This “dual-action” is where the Porter Cable 7424 gets its “DA” nickname.

Here's a great example of what the Porter Cable 7424 can do when used with Sonus polishes and foam pads.   As you can see, even a badly oxidized finish can be restored to a nice shine.

If you have previously owned a random-orbit car polisher that made a lot of racket, but did little else for your car’s finish, you will appreciate the 7424 as a "professional grade" machine.   Most consumer “car polishers” don’t have enough power, have a very small orbit (often less than 1/4 inch), and have limited accessories. The Porter Cable 7424 is the first machine to shatter these limitations.