Yamaha Polyester Marks

[Paul McCloud]

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