Your AC chips should clean up well. I have tried all the cleaners and I just keep going back to the common mechanics hand cleaner with Lanolyn like Go-Jo. Not the stuff with "grit" in it but stuff like GOOP that is a cream. Cover the chip and let it sit for a few... follow with a gentle brushing with your old tooth brush...rinse off briefly under the tap using your fingers... gently dry with a terry towel...allow the chips to air dry completely before stacking them. If the chip is really full of crud like the Top Hats are full of crud...GENTLY use a round wooden tooth pick but discard them if they bend or break...then...repeat the GOJO process. If at any time you see color coming off the chip, STOP! This will work well on common $1 casino chips made in the last 20 years or so but if it is an old chip or a rare chip leave it alone or get a pro to do it. Good Luck. Smitty