Killer Octave Question

[Delwin D. Fandrich]

----- Original Message -----
From: "Greg Newell" <gnewell@ameritech.net>
To: "Pianotech" <pianotech@ptg.org>
Sent: Saturday, April 12, 2003 8:02 PM
Subject: Re: Killer Octave Question


> >If the crown was created by being deformed for many years we would see
all
> >piano makes with this feature. If this were so they all would have
crowned
> >bridges. But clearly some makes have crown and others don't.
>
> Good point! I haven't seen enough of them to make this comparison.

Not necessarily. It would depend on how rapidly the original board lost its
compression-crown. If the original board was set up (in NY or wherever) on a
dry day with a fair amount of string bearing and then sent to a relatively
humid climate it would deteriorate quite rapidly. There would not be enough
time for the ribs to take on a set themselves. On the other hand if the
board were originally set up on a humid day and with light string bearing it
would last considerably longer. As to whether this would be long enough for
the ribs to take on a set or not I can't say. I have pulled ribs off of old
Steinway boards that indicated some slight amount of curvature. (I would
call 1/8" curvature on a long rib "slight.") Both up and down. I'm not
prepared to say just where this curvature came from. Steinway has
traditionally installed flat ribs. While it is certainly possible for a flat
rib to warp though it would be unlikely for three or four adjacent ribs to
warp in the same direction.

Del