> "OK ?" OK.......but! Are we really sure that a varnish/laquer covered spruce panel would absorb more moisture than an unprotected piece of maple/hornbeam/walnut (or whateverelse and action is made of)? Certainly the large panel would change dimension TONS more because of its overall size, but per unit volume, I would almost be suprized to find that it does. (I'm trying to be constructive and informative - not step on anyone's toes!) Is this a question for Del to chime in on? Terry Farrell Piano Tuning & Service Tampa, Florida mfarrel2@tampabay.rr.com ----- Original Message ----- From: "Tony Caught" <caute@optusnet.com.au> To: <pianotech@ptg.org> Sent: Saturday, December 30, 2000 9:36 PM Subject: Re: Wood & Humidity, was Hammers > 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 > >
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