Hi Alan,
We build and replace everything inside the action compartment for Steinways and most other pianos (including keyframe, keys and stacks). But I don't see water damage situations very often though, it's usually age, wear or poor repairs that are the culprit.
My only really concern is the key bed. Even if you replace everything in the action compartment, will the key bed be stable? I would give the key bed a month or two to dry with DC heater rods, then test it with a moisture content meter. The meter we use and trust is made by Lignomat. It uses radar to gauge the density, you have to tell it what kind of wood. It's really accurate but cost is about $200. I have an extra unit which I could send as a loaner after the key bed dries, after say a month or two.
Once the key bed moisture content drops below 9 or 10% it will probably approach a stable state. At that point check how flat the key bed is with a straight edge, both front to back and bass to treble (and for cracks). Then check it again in a few weeks and if it has not changed, a new action may be worth pursuing. If there is a very slight stable curve in the key bed that was induced by the water, a good rebuilder should be able to sand and plane to match a new keyframe.
If I had the piano (or keybed) here in Michigan, I would place the keybed in my wood drying kiln for long enough to get it down to below 8%. Then acclimate it to my shop for two to four weeks or so. Normally kiln dried wood that measures 7.5% to 8% comes back up to about 9 to 10% MC with that procedure. I believe it would be stable after that. Assuming the rest of the piano just got high humidity for a short while, then it seems a crying shame to total the piano for a keybed.
This is the same treatment we give already commercially "kiln dried" sugar maple, white oak, ash, spruce etc... for building key frames. We have no issue at all with stability, our keyframes stay perfectly flat.
(this was posted in CAUT also, sorry for the repeat).
Hope that helps,
Best regards,
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Dean Reyburn, RPT
Reyburn Pianoworks
Reyburn CyberTuner
1-616-498-9854
dean@reyburn.comwww.reyburnpianoworks.comwww.cybertuner.comwww.martysmasks.com Facebook:
www.facebook.com/dean.reyburn------------------------------
Original Message:
Sent: 12-31-2020 09:49
From: Alan Eder
Subject: Aftermath of water damage
Greetings Lists,
A burst pipe in the ceiling above a thirty year old Steinway L resulted in water entering the action cavity. An initial survey indicates that the soundboard, strings, bridges, rim, damper system and pedal lyre all appear to have dodged the bullet. However, the action cavity took on water, soaking parts of the keybed, keyframe and some of nearly every kind of main action component. The key slip is now bowed by 5 mm. Some of the string rest felt in the lower capo is wet.
The first thing I did yesterday was to move the piano out of harm's way and take the action apart so things could be spread out to dry. Planning to return today with fans (to improve air circulation), bakers' cooling racks (to better expose all sides of the keys to air), a heat gun to hasten the drying of the string rest felt, and an array of Dampp-Chaser drying rods to suspend under the piano. Upon the advice of Richard Davenport, RPT, I will put blocks under either end of the key slip and a weight in the center, in an attempt to counter-act the bowing.
My questions are:
1) What else should I be doing at this stage to help dry things out?
2) Is there any hope that the keys, keyframe and key bed can be made functional and reliable once dried out?
3) Is anything short of complete action replacement going to be reliable?
Thanks,
Alan
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Alan Eder, RPT
Herb Alpert School of Music
California Institute of the Arts
Valencia, CA
661.904.6483
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