high humidity , possible reaction to crumbling rubber grommets , The part is a key end fork. Look for rust on other metal parts including tuning pins, coils , screws , bracket
Not sure what your humidity is like there but the piano may have been in many places before you saw it. You could try using a Rustoleum product on all of them to treat the rust and prevent it . There used to be a bluing solution that could be put on tuning pins and coils it was very effective . Schaff supply carried it and I think it can still be purchased from some metal supply companies
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James Kelly
Owner- Fur Elise Piano Service
Pawleys Island SC
(843) 325-4357
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Original Message:
Sent: 02-18-2026 15:00
From: Neil Vanderschaaf
Subject: Rust on the key end spades of a lift action (spinet) piano
My adventure in piano repair today involved replacing the rubber grommets on a Wurlitzer spinet piano. This grommet fits into a metal spade driven into the end of the key. I am trying to figure out why some (maybe 10%) of those metal spades were very rusted while the rest were not (ie: zero, zilch absolutely no rust at all). There didn't seem to be any pattern to it (like what a spilled drink might cause). Any thoughts on why this might have happened and how I can prevent it from happening again would be greatly appreciated.
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Neil Vanderschaaf
Round Rock TX
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