Don't worry about it, pad is more eraser like than abrasive. I couldn't determine any damage to track from it. I found it would gunk up rather quickly. Matter of fact, lot of guys get dry wall abrasive and add strips to the pad to make it work better! Adding some pipe nipples with bb's or pellets siliconed inside on top of the floating part of the car also helps effectiveness.
By the way, adding a rough geographic location to your profile would help in answering many questions you might pose. State name, region, or the like, just to give folks some idea of your climate and stuff like that! Operating conditions are indeed different when comparing the frozen tundra to the West Texas heat, or the dampness of the Atlantic coast to the arid desert regions!
And to cut the grease and grime, LGB suggests clreaning pads should have their smoke fluid added to the pad as the LGB fluid is both smoke and cleaning fluid.
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