NY Steinway Ribs and MC

[Farrell]

I don't know what the exact implications would be with let's say panel 
ribbing done at 5.5% vs 4%. Obviously, with everything else being equal, the 
4% would develop more crown. But I've never built such a board. I do know 
that ribbing done in the range of 6.0% to 6.5 % doesn't develop much 
compression crown at 50% RH room conditions. I really don't know, but based 
on my very limited experience with compression crowning, I should think that 
ribbing done at 5.5% wouldn't produce enough crown for a compression crowned 
board - but then again, we don't know the radius (radii) of the cauls used 
when pressing - do we? You don't have to dry a panel down at all to produce 
a compression crowned soundboard if you press the straight ribs and panel 
into a small radius enough caul.

Dunno.

Terry Farrell

----- Original Message -----
> Yes... that was the only real difference.  5.5 % versus 3.8%-4.5% 
> depending on the season.  As to the significance I attach to that 
> difference, I dont think I need tell you about any of the implications 
> there :) Thats quite a large difference if these are glue up stats.
>
> RicB