Porter Cable 343K vs air radom orbit sander

[** Frank **]

started using my new PC 343K and it doesn't seem to be aggressive. When the description says it does 12,000 orbits/minute I guess it does those tiny

12,000 random vibrations per minute and not really turning the pad at 12,000 rpm.

On the other hand, my air driven random orbit sander which I had for couple of decades, is extremely aggressive in both random and rotation action. The air driven one is more like a real disk sander with orbital action while the PC is more like a pad vibrator with some disk rotation. So am I correct or either I'm not using the PC correctly or its defective?

[Charlie M. 1958]

Nope, that's just how it works. I think the slow turning of the pad is what makes the orbits "random".

[alexy]

I don't have the pneumatic tool point of reference, but I had the same reaction when finally buying a ROS. I had heard so much about how good it was at removing stock. Found that it was true, but I needed to change the way I thought about it. It was not more aggressive than my vibrating pad sander--it was smoother. With that frame of reference, you can get to more aggressive by a different route; the ROS with

60-grit will remove material much faster and provide a similar finish to the vibrating sander using 120-grit.

(And, no, I haven't tested these two grits for comparability of finish--just using them to illustrate the concept.)

[Phisherman]

I'd expect an air-driven tool to be much more aggressive and lighter than a unit with an electrical motor. A ROS is closer to a finishing sander. If you want an aggressive electric sander, consider a belt sander.

[** Frank **]

I have couple of belt sanders, both Craftsman. One purchased from the late

70s is a PIA as the belt wonders all over the place. I also inherited a commercial/professional Craftsman belt sander - looks real good but need parts.