Micromarring and smaller scratches can indeed be removed and lightened with the use of a machine buffer like the PC-XP. You always want to start with the lightest polish and pad combo and move more aggressive only as needed.
If you have the Wolfgang/Lake Country pads then likely a white pad (medium) and Zaino ZPC will be a light combo and should help. You can always move to a more aggressive polish (often called swirl removers and numbered based upon cut) or to an orange (abrasive) pad. I have never used an orange pad and ZPC so would suggest speaking with Frank (aka AgentF1) or Sal first to get best hints. Other polishes like Megs 105, Menzerna SIP, and even 3M should work also.
Often times when using a more abrasive pad/polish combo you need to come back to a lighter pad/polish combo to remove smaller markings and micromarring. While it doesnt sound like you are in this predictament now, it might be needed later. If the marking is quite light and really just want to clean paint a bit and boost the gloss and reflection then move straight to a finishing pad and light finishing polish.
http://www.autogeek.net/detailingtips.html
(this should help too , and please contact us if additional help is needed).
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Porte Cable 7424XP Polisher ??????
