Those lines and dull marks that you find when two pieces of high gloss polyester rub together require sanding before you try to polish out. If you look closely, you'll find tiny "holes" which are the result of dust particles pushed into the finish. You will need to sand them out before you polish it, or you'll be rubbing forever trying to get the finish polished out. I always try to warn new piano owners that the finish is very soft, though it is tough. I recommend some kind of soft cloth in between the two parts so this kind of thing won't happen. Webb Phillips is a good source for polishing compounds. You can also get them from a plastics store where they have compounds for polishing plexiglas and lexan. Meguiar's Mirror Glaze Co. makes compounds for plex, use their #10 and #17. Sanding, use at least #1200 grit, wet/dry paper from your local auto body supply store. They will likely have the Meguiar's products also. There is another company, Esquire Piano, near the Yamaha factory in Buena Park, that will give you advice and supplies for doing polyester work. Call Yamaha for their number. They do quite a bit of work for Yamaha. If that's not enough info, Mohawk has their polyester polishing kit, which we use in our shop extensively. The elbow grease is up to you. Good luck! Paul McCloud
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