<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META content="text/html; charset=iso-8859-1" = http-equiv=Content-Type> <META content="MSHTML 5.00.2614.3500" name=GENERATOR> <STYLE></STYLE> </HEAD> <BODY bgColor=#ffffff> <DIV><FONT face=Arial size=2>From time to time I open an upright and = find the pressure bar and screws coated with a light yellow-green powder.  = What is this?  Oxidation?  How should I clean this off, or should = I?  Saw one yesterday on a Wurlitzer spinet (2-pedal).</FONT></DIV> <DIV> </DIV> <DIV><FONT face=Arial size=2>Thanks --- Doug Garman  = :o)</FONT></DIV> <DIV> </DIV> <DIV> </DIV></BODY></HTML>