Soundboard drydown for installation

[Richard Brekne]

Yes... and I get the sense a bit of this is being mixed up here with 
talk of whatever potential benefits there are to drying down the ribbed 
assembly just prior to installation in the case.  Concerns about cracks 
appearing, be they compression spawned or just pulled apart because of 
too little drying are about how dry the the panel is just prior to 
ribbing.  I cant see that has anything to do with whatever potential 
benefit there might be to keeping the thing dry while the ribs glue 
cures, or re-drying just before you glue the whole thing onto the rim.

I am curious tho to what this bit with Steinway Hamburg is... they said 
it was <<crucial>> to getting their bridges right.  As it happens I will 
have the chance soon to ask them again so I will see what I can pump 
from them.

As for CC ridges in boards made in Europe. This is far from a Steinway / 
Grotrian phenomenon.  I'd say the greater portion of European produced 
pianos display this kind of thing nearly in every case. Petrof, 
Schimmel, Steingræber, Seiler...  I've personally talked with their 
design people and they say outright compression ridges are a sign of a 
well put together board. All of these and a good deal others also 
mention figures like 3.5 % EMC before gluing ribs.  Udo Steingærber just 
told me in Helsinki in October this is necessary for the European 
climate... and he also told me they make as tight a fit as is humanly 
possible in gluing their assemblies into the case.  I will be seeing him 
again before long as well... so I may get a chance to see them doing 
what they do first hand.

Cheers
RicB


    I should think the moisture content of the panel at rib glueup
    should be
    much more influential on the propensity of panel cracking rather
    than the
    moisture content of the soundboard at installation time.

    Terry Farrell