What's the difference..!

[Joe's detailing]

Between the porter cable (7424) and (7428)
I can get either one new for $100

[kpagel]

Re: What's the difference..!

The 7424 is a dual action polisher while the 7428 is a rotary. Totally different machines.

[Mike Phillips]

Re: What's the difference..!

As far as we know nothing about the tool, one might come with a foam pad or without a foam pad or some other accessory. Some models have a different counterweight to accommodate different size backing plates but this appears to only matter when using the tool as a sander, i.e. you have a backing plate with a piece of lightweight sandpaper attached.

No noticeable difference when you have a foam buffing pad attached and the pad becomes heavier with use from saturation with liquid products.

You should be able to go to PorterCable.com and find out any differences or optional accessories.

[Michael Stoops]

Re: What's the difference..!

The 7424 is a dual action polisher while the 7428 is a rotary. Totally different machines.

Right you are - I have both machines. The 7424 is the defacto standard for dual action polishers, AKA the DA, G100, PC, etc. Whenever you see those acronyms used it is almost always referring to the Porter Cable 7424. A bit of a learning curve to achieve great results, but in the process you really can't do any damage. Just don't drop it on the hood of your vehicle!! With some practice, the proper technique and the proper pads and chemicals you can do a great job of removing swirls, fine scratches, water spots, and oxidation. It may take a pass or three to get things done, but it's a great tool. It does not simply spin the pad a high speed around a central axis, but rather oscillates the head of the machine, thereby spreading out the work a bit, and producing much less heat than a rotary buffer. This is what causes it to work a bit slower than a rotary, but also makes it much safer.

The 7428 is a true high speed rotary. In skilled hands it can make very short work of serious defects, but in the hands of a novice it can literally burn and destroy the paint. Sure, that's the worst case scenario, but it happens. It's also very easy to polish right through the paint on high spots along sharp body lines and where panels line up (or line up less than perfectly). If the learning curve on the DA takes some time to get through, this one is even more critical simply because of the potential for damage. Be very careful with this machine if you don't know your way around it.