Dumb PC question

bigpoppa

New member
As the title states, this is a dumb question. Does the pad on a PC rotate or something else? I was under the impression that it didn't rotate in the rotary sense. I have searched but didn't find anything on point.

:confused:



Thanks, everyone.:wavey
 
The pad attaches to a plate with velcro. The plate is attached to the motor. That is technicly what spins. The alternative is to attach your car to the velcro plate and then just stand in one place with the pad. :D



The pad orbits and rotates. Kind of like the earth orbits and rotates around the sun. I don't think it can be drawn out in here really. If you can imagine the earth example then you'll understand. :up
 
Jngrbrdman said:
The pad attaches to a plate with velcro. The plate is attached to the motor. That is technicly what spins. The alternative is to attach your car to the velcro plate and then just stand in one place with the pad. :D







I guess that wasn't the best way to phrase it - I meant the pad does something else other than rotate rather than something rotating other than the pad. sorry about that. :)
 
Ds01C5:

It's not a dumb question at all.

Your original impression is pretty close. The PC backing plate and pad moves in a very small orbital pattern. It does not rotate in the true sense of the word. Put a pad on, set the speed to 1, and hold the pad while turning the PC on. The pad will not rotate around the centerline of the mounting point for the pad. It will move in what is almost a vibrating or jiggle motion if any resistance is applied. If no pressure is applied, it will turn or rotate around the center driving point. It is hard for me to describe, and I have no idea how it works. Another good way to see the actual motion is to use BradB's PC and MF system for removing product. When you are on a flat, clear surface the MF will rotate very slowly. When it meets some resistance, it will stop and have just the vibrating motion. The pad and the MF will not turn at all.



Charles
 
Yeah Charles pretty much covered it. The pad moves in an orbiting motion like if you were doing circular-style polishing with your hand. It does feel like "jiggling". The pad does spin some, but it's only a byproduct of the orbital motion, so how fast it does this depends on how much pressure (resistance) you press down on the machine.
 
Let me take a stab at it...



First, imagine drawing a little circle on the table. Then, take the backing plate and trace out the circle with the shaft on the plate. Or better yet, imagine the shaft of the backing plate had ink on it. Try to draw a little circle with the backing plate. This is the motion the machine makes with the pad. It moves the shaft of the plate around tracing out a little circle. This would be the orbiting motion of a PC (nothing random about this orbiting motion).



Now, forget that and imagine a bearing that was attached to the table. If you put the shaft of the backing plate in it, it would allow the plate to spin freely. You could spin it however you want, and it would be just like a wheel spinning about its axle (it doesn't trace out a circle, it just spins). Because the pad can spin any way it wants to (any way you push it), the motion of it would be fairly random (predicted by anything external that pushes it).



Lastly, imagine combining the two. Have the bearing trace out an orbit, causing the backing plate shaft to also trace out a circle. However, the plate itself is free to spin any way it wants (or not at all) while it is tracing out this circle. While the shaft isn't moving in a random motion (it is forced to trace a circle), the face of the pad is random because while it is rotating, it can be spinning in any direction it wants to. This gives the face of the pad a sort of jiggling motion.
 
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