Wood & Humidity, was Hammers

[Tony Caught]

Hi Terry

Gee wiz and golly gosh. My mistake I should have been more explicit and said

"Both spruce and pine that are used for making soundboards are soft timbers,
cut on the quarter which promotes swelling of the soundboard.  These soft
timbers will of course accept moisture more rapidly than the hard woods that
are used in the making of actions in the same piano."

Am not into timber boat building, only interested in pianos and aluminium or
fibreglass boats but thanks for the info.

PS I guess I should also make a correction to the above by adding that
"Other timbers have also been used for making soundboards with varying
degrees of success however the varieties of the above mentioned timbers that
are used, today, for making soundboards, are of the softer variety".

OK ?

Regards

Tony Caught ICPTG
Australia
caute@optusnet.com.au

----- Original Message -----
From: Farrell <mfarrel2@tampabay.rr.com>
To: <pianotech@ptg.org>
Sent: Sunday, December 31, 2000 3:16 AM
Subject: Wood & Humidity, was Hammers


> >" Both spruce and pine are both soft timbers, cut on the quarter which
> > promotes swelling of the soundboard.  The soft timbers will of course
> accept
> > moisture more rapidly than had woods."
>
> I don't think the above statement is necessarily true at all. Both spruce
> and pine are "softwoods". All spruce and some pine woods are soft. Some
pine
> woods are extremely hard. Some "hardwoods" are soft and some are hard. A
> "softwood" cut at a time when much resin is present in the wood may make
the
> wood less susceptible the water content gain from high humidity.
"Hardwoods"
> can vary to extremes on their ability to pick up moisture from the air -
> largely based on their cell structure. Trees have interconnected cells
that
> allow water movement from the roots to the leaves. These cell can large or
> small diameters. Also, upon a cell's death, the cell ends may close or
open
> up. A species group such as red oak (certainly a very hard "hardwood") has
> both large interconnected cells and the cell ends are not present after
cell
> death. Cut a six-inch long piece of red oak. Put your mouth up to one end
> and blow. You can feel the air coming out the other end (or dip one end in
> water and you can make bubbles!). Certainly these kinds of structures open
> up such a wood to rapid changes in moisture content. The white oak group
on
> the other hand has little end caps on each of the same cells, thus
> preventing water from flowing through the wood. That is why they make oak
> wine and whisky barrels out of white oak - because liquids will not pass
> through. These are some of the properties that give white oak many uses in
> boatbuilding and make red oak a big No No in virtually any boatbuilding
> application.
>
> Terry Farrell
> Piano Tuning & Service
> Tampa, Florida
> mfarrel2@tampabay.rr.com