I believe to make the PC the most effective that the pad
should indeed spin. This way the pad not only jiggles into the paint but it also rotates ... which I would see more effective than just the jiggling. As Al said, check out this thread that I made the other day:
http://www.autogeekonline.net/forum/...deos-pics.html My 7.5" pads spin and jiggle, so I see no reason why your 6 inch pads do not.