What kind of chips Brian? Some good advice here already and of course, it's your personal choice! Hard to hurt a newer on-the-table-now inlay chip, scrub away but be very careful with any hot stamp. As for older or obsolete chips, puleeze be very careful. I've got an example of a chip that is a roulette overstamped with an inked "$1.00" that enhances the chip in my eyes. It was probably cleaned by someone who didn't see the overstamp notation in C/W Official Guide... but one side survived somewhat while another example of the same chip that I own was cleaned until the stamp was gone. Also just acquired a seldom seen old-timer whose hotstamp color was completely removed even though the chip was in very good condition otherwise. If you clean chips for your personal collection like I do (ever heard of "filthy lucre"?), gain experience with some newer inlay chips first.