To a certain extent, the bus has left the station in that once started it can't be reversed and will tend to accelerate over time. It also progressively degrades the tonal quality.
I'm a little suspicious as to whether the piano cover is the sole culprit. Is there noticeable rust on other metal fixtures in the room such as window frames, hinges or electrical fixtures? How do the pedals and leg ferules look on the piano?
There are electronic humidistats that will record over time for pretty low prices, you can put it inside the pianos and get read outs on a phone app and they record a month of data. Learning about the 24 hour cycle is helpful.
Some people recommend a product called Bullfrog rust inhibitor. The type put in pianos comes in a 1/2"x12"x12" perforated cardboard box and emits a chemical that binds with metal to inhibit rust. The local piano dealer includes them with all his pianos. It was discovered here in the islands because the US Navy buys it in liquid spray form by the case. It can be found on amazon. People also use it in one form or another in shops, gun safes, etc. It won't solve your problem but might slow it down.
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Steven Rosenthal RPT
Honolulu HI
(808) 521-7129
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Original Message:
Sent: 04-05-2025 16:35
From: David Pinnegar
Subject: Acceleration of rust on strings in a heated church - is a quilted plastic cover to blame?
Thanks so much. Good idea and I'll find a cheap hygrometer to put inside so at least we'll know a measurement when we open it.
Not being quite sure what we're talking about with respect to a "string cover" as English can be a different language across the pond.
Best wishes
David P
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David Pinnegar, B.Sc., A.R.C.S.
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+44 1342 850594
Original Message:
Sent: 4/5/2025 3:24:00 PM
From: Patrick Draine
Subject: RE: Acceleration of rust on strings in a heated church - is a quilted plastic cover to blame?
David, I suggest buying a data logger that will provide information the variations (or not) in humidity and temperature. You can print out a graph of the variations which will make explaining things easier when discussing it with the priest, music director, et. al.
And Paul McCloud's suggesting the proper usage of a wool string cover (in addition to the cotton quilted cover) is very good advice.
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Patrick Draine RPT
Billerica MA
(978) 663-9690
Original Message:
Sent: 04-05-2025 07:36
From: David Pinnegar
Subject: Acceleration of rust on strings in a heated church - is a quilted plastic cover to blame?
A Yamaha C3 is in a small church and kept covered by a standard quilted cover.
The church is well used and heated modestly, but doesn't have openable windows and the doors are always kept shut, so no ventilation. The priest swears that there is humidity control although I've never seen it.
People coming in for services will be introducing humidity into the atmosphere and I don't see how it can escape. A candle burns continuously about 10ft away from the piano.
15 years or so ago the strings were in perfect condition. Rust started appearing and seems to be accelerating.
If there is (invisible) humidity control, I'm wondering if the non-breathable cover is to blame. The instrument is opened for services and concerts, with people raising the humidity, and then closed and covered. I'm wondering about recommending that the instrument should be left with the lid down but open, and covered merely with a dust-sheet or other such cloth?
Best wishes
David P
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David Pinnegar BSc ARCS
Hammerwood Park, East Grinstead, Sussex, UK
+44 1342 850594
"High Definition" Tuning
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