I am asking this question for a fellow technician who does not have net access. He has a piano to service that has one of these tops that is hinged so that it folds back in half. Some water dripped down through the crack and got onto some of the damper felts. It missed the hammers, but affected the dampers. Now, they make that "yick" noise when they contact the strings, when the key is released, making us think they have gotten hard. Is there any way to re-soften them. I have tried needling them, but with almost no success. I have heard that lanolin can be brushed into them, but want to confirm that it works before trying it. Or, must he just replace them? There was nothing wrong with them before contact with the water.
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