Alternatives

[Danny Moore]

Bob,
Interesting that you should consider the use of composite materials.  I
have a
customer that spent 30 years in that industry before selling the
business and
retiring to a life of sailboat racing, etc.  His first success was in
the late
60s as the designer of the Chaparal race car chassis.  You may recall
that it
was constructed of all composite materials.  Since his first love is
sailing,
he has designed many of the high-tech America's Cup yachts and many
other
racing boats constructed from composite materials.  The entire 2nd floor
of his
modest, 3-story waterfront home is filled with trophies and photos of
his
accomplishments.  Like your new engineering friend, he's an interesting
cat.

Anyway, I suggested that he consider the use of composite materials in
the
manufacture of say, soundboards, bridges and/or pin blocks.  (Especially
since
he drove me nuts wanting to know each thing I did as I rebuilt his
piano.)  He
stated that he has given some thought to the idea, and determined that
composite material exhibits too much "creep" to be used for sound
boards, etc.
He says that composite materials tend to take on a "set" based on
loading
factor at rest.  A desirable feature in the manufacture of auto chassis
and
yacht hulls, but not acceptable in sound boards.  He thinks that the
board
would take a set and behave as if it were "dead" even though it
exhibited a
measurable crown.

Run this by your friend.  I'd be interested in his thoughts.

Danny Moore
http://www.setexas.com/danmoore/

robert sadowski wrote:

> Dear List,
>     Happy Easter to all.  Through my future wife I have struck up a
> friendship with an engineer whose expertise is in the area of new
> materials - carbon fibre, etc.  We had a long conversation about pianos,
> soundboards and such.  He is fascinated by the choice of materials used in
> piano construction and of course asked the question - why can't other
> materials be used to replace spruce in soundboards.  He asked me to try and
> locate sources of data concerning stresses, density, mass, and how
> soundboards in general do what they do.  Any suggestions as to published
> sources?
>
> Thanks,
>
> Bob Sadowski