PC vs Rotary

[former86camaro]

I have the PC and I have the Chicago Electric Rotary (LOL).



A buddy asked me “how can a rotary that moves at slower speeds be better at defect removal?�





My first assumption is because it works a smaller spot generating more action and heat on that spot?





Please help me explain the benefit of the rotary in layman’s terms.





I use mine when the swirls are bad on cars, but I get a lot of sling and usually the effort of it does not seem worth it. Most likely it is the Cheap Rotary.

 

[imported_Sullybob]

The rotary is direct drive and the PC is a random orbital drive. So all of the force from the rotary is concentrated in one spot (like a drill) where the PC moves in a random orbital pattern (simulating your hand) spreading out the force and the heat.

 

[the other pc]

...A buddy asked me “how can a rotary that moves at slower speeds be better at defect removal?�...

He’s confusing motor speed with pad speed. They're not the same thing.



With an orbital, every point on the pad moves in an arc the size of the orbit, which is only a fraction of an inch.



With a rotary the speed at which any point on the pads moves is proportional to its distance from the center. That’s up to a six inch diameter arc for a six inch pad, an eight inch diameter arc for eight inch pad, etc.



So if a point on an orbital pad is moving at four times the rpm's but the distance to that same point on a rotary pad is forty times the diameter of the orbital's orbit, the point on the rotary pad is still moving along the paint at tens times the speed as on the orbital.

PC.