I am working on the new set of dampers on a Baldwin SD-10 and having problems getting them to silence completely. I found a broken damper underlever flange and had to pull it out. I took a look at the felt wedge that holds the spring in place - the spring that pushes the underlever back down. Inside of that felt wedge was a black mess of something - old lube I suppose that had perhaps collected dirt - I wondered if this might be gumming up the work of that spring and slowing down the underlever? To clean it, I think I would have to pull the entire back action, put new felt wedges on and clean the springs. Big job. I used protek on all of the underlever flanges.
Also, I used Tokiwa felt and the damping is insufficient in a rather wholesale manner. I have tried to follow every normal procedure. The tenor dampers especially have an over-ring (almost like a harmonic) sound that doesn't seem related to sympathetic vibrations of other strings because as soon as I touch the string I played - it stops. Is the Tokiwa felt dense/soft enough? I have even tried substituing flats in the back instead of wedge - and got a tiny bit of improvement but not enough.
Any ideas are appreciated.
Bob Hull
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