PC Question For The Pro's

Discussion in 'That'll Buff Right Out' started by jjski78, Jun 15, 2007.

  1. jjski78

    jjski78 New Member

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    Ok, so I recently bought a PC with a set of 6.5" Lake country pads and a couple of 5.5" wolfgang pads. Today I started to work on my truck using the PC for the first time in my life. I was using a polishing pad with Optimum polish and I'm noticing a problem. All of the EDU's and how-to's that I've read regarding the PC say to not apply any pressure and let the weight of the machine do he work. Well, I was doing that, but it seems that maybe the machine is too heavy for itself?? I had it on a setting of 4.5 and it was making a god awful grinding noise and seemed to only rotate and not do it's DA jigging motion. If I lifted slightly on the machine, it would quiet down and resume it's jigging, but the I wasn't geting hardly any pad contact. Well, I polished my hood, and found some spots that needed heavier cutting. So I swapped out the 6.5" polishing pad for the 5.5" light cutting pad and started to polish. And the machine didn't do the previously mentioned crap when put on it's full weight. With the 5.5" pad installed it worked like a dream!! So my question is this: What would cause the machine to not operate properly with the 6.5" pad, but work perfectly with the 5.5"?? I used the same backing plate both times, a 5" flexible one. Could it be that maybe I need the 6" counterweight?? The one installed says for use with 5" pads only. Any help would be great!!
     
  2. n2_space

    n2_space Space > *.*

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    You should put enough pressure on teh PC to to make it bog and not rotate, then let off a hair. If you mark your backing plate with a sharpie, it's easy to see. You will use about 15lbs of pressure. Using a PC without pressure will get you no where. Rotaries are the ones you let the weight of the machine handle it without pressure.
     
  3. Scottwax

    Scottwax Making detailing great again! Moderator

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    http://forums.offtopic.com/showthread.php?t=2517501

    Using a polishing pad, apply a circle of product about 1" from the edge of the pad and for the first couple of areas, before turning on the PC, spread the product over a 1' x 1' area to prevent dry buffing. With the pad pressed lightly against the paint, turn on the PC and set it to '5' and spread the product over a 2' x 2' area using moderate pressure. Kick the speed up to 6 and slow down your passes to about 1/2-1" per second with 50% overlapping passes, up/down, across, diagonally. Use enough pressure to lightly bog the PC and then back off just enough to pick the speed back up. Work the polish until it begins to clear or dry. Wipe off excess product, inspect your work, one or more additional applications may be needed with heavy defects.

    I've used both the 7424 (5" counterweight) and 7336 (6" counterweight) with 6.5" and even 7.5" Lake Country VC pads with no excessive vibration or noise. FWIW, smaller pads do cut faster than larger pads.
     

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