I think Kimball had a special problem with some models of spring rails. I seem to recall the dye in a particular kind of green felt had a chemical that reacted with metal, so all the hammer butt springs corroded and broke. More often, though, the cause of broken springs was mice sitting on the rail to nibble on the hammers, and they, uh, "leaked" on them. Quite corrosive. Take the felt off the rail. Use pliers and pull what is left of the springs off. Take new springs, insert them in the rail, bend them into position, and use hot glue from glue sticks in a glue gun to keep affix them. Not a big deal. Carol Beigel
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