Andrew writes: << If crown needling between the grooves doesn't get me any "bloom" are we talking replacement hammers, acetone wash or what? >> There are several things to try before replacing them. A soaking with acetone might move whatever hardener away from the center of the hammer, but it is hard to tell. (if shellac were used, acetone will not do anything). I would be inclined to try steam. I did this last week to a stage piano that had sufficient hammer weight left, but not flexibility. I use a 1" wide strip of old flannel bedsheet. I soak it in water and squeeze it out as hard as my hand can go. I then lay it on the shoulders of the hammers, a section at at time. One edge of the strip is aligned at about 11:30 on the hammer (viewed from the side as a clockface, crown is 12:00) so that the strip is never right on crown. With an iron set on "cotton", I make one pass along the section, rather rapidly. There will be a wisp of vapor coming off the cloth behind the iron. Then I repeat on the other shoulder. The results can be profound and immediate. You may need to do a light filing if the felt distorts, and you can repeat it if nothing happens. good luck, Ed Foote RPT http://www.uk-piano.org/edfoote/index.html www.uk-piano.org/edfoote/well_tempered_piano.html
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