At 19:44 +0100 17/1/08, Stéphane Collin wrote: >So I asked for their standard procedure, which I think is quite nice, as the >board was nicely crowned at 40 % humidity. Hello Stéphane, I'm sorry to hear of your troubles, but they may turn out to be less disastrous than you fear. Let time do a bit of work for you and see if there is any real damage. In a posting in November I described briefly the traditional English way a soundboard is made : <http://ptg.org/pipermail/pianotech.php/2007-November/213166.html> and I presume the Italians follow the same sort of procedure. As you see the only drying out involved is when the glued-up board is put in the drying chamber _before_ the ribs (these _not_ dried out) are glued on. The crown develops as the board re-absorbs moisture from the normal environment, and once it has done so and settled down, it is ready to be trimmed to fit, the bridges fitted, the underside varnished, and glued in. There is absolutely no need to dry out the soundboard (and ribs!) once the thing is made, and I presume it could be pretty harmful, though a lot less harmful than drying it out after it's stuck in -- and you have enough evidence of this from the old Bechsteins you have seen! It is no Your humidity figures I find rather astonishing: At 19:44 +0100 17/1/08, you wrote: >Apparently, I dried the board too much, as it went reverse crowning. >Strange enough, after 24 hours back in 40 % 22 ° celcius environment, the >board still remains reverse crowned. I'm fearing something irreversible >happened. I am lucky to achieve double the first and half the second at the moment, so I envy both you and the Val di Fiemme such warmth and dryness, but I'd suggest you take the soundboard somewhere old-fashioned for a while and let it breathe in a bit or real Belgian air. JD
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