I've had good results by hand, soft cotton cloths, with Meguiar's Mirror Glaze Ultra Finishing Polish.
Found in auto supply houses, professional paint centers or online. If it doesn't fully eliminate the fine scratches you may have to go to a 'grittier' grade, then buff back up again. Can also be used with electric buffing wheels but I don't want to risk having it fly off the piano into a clients furniture or rugs. So I use elbow grease to apply.
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Michael Hagen RPT
Rohnert Park CA
(707) 664-9857
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