List et all Very Interesting, I have been carrying a research on this subject, I tried fabric softener a long time ago and I had both results, so got to the bottom of the matter. one of the reasons for hammer and dampers to harden is that they loose their natural oils, Fabric softener is nothing else than a very light natural oil mixed with a chemical agent in an emulsion what eventually rusts the strings, and hardens again is not the oil, but the chemical used, that doesn´t happen when you wash, because the chemical agent will dilute in water and the only thing left is a very small amount of oil. I had good results diluting "Lanolin" 1 part in ten in thinner or benzene or you could search for any fast drying solvent which won´t leave residue. Once its dry I steam it, that way you you are returning natural oil to the fabric and steaming it gives it fluffiness. That is my comment Elian Degen Piano Tuner and Technician Caracas, Venezuela
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