<HTML>Thanks Marcel,        I'll look for that source of powder in = the future.  In this piano, however, both rails had felt. The powder wa= s spread over the tops of the keys after the key button.  I found no po= wder in the action.  There was also the taste of copper from the airbor= ne dust.          If I see this powder again and no foame= d rails, I'll close up the piano.  It is very fine, nasty powder and quite difficult to clean out without inhal= ation. George Tyson, Associate Klamath Falls, Oregon George, I've seen some spinet which = had some kind of foam instead of felt for the hammer spring rail and hammer = rail in some cases. This foam was originally green but with time it just bre= aks up and could have created the condition you have seen. The foam become l= ike dust only where the damper wire touch it and under the hammer shanks. Ch= eck it out again. Marcel Carey, RPT<FON= T COLOR="#000000" style="BACKGROUND-COLOR: #ffffff" SIZE=3 FAMILY="= SANSSERIF" FACE="Arial" LANG="0"> Sherbrooke, QC   </HTML>