Soundboard crown & carbon fiber & cellos

[Delwin D Fandrich]

----- Original Message -----
From: "gordon stelter" <lclgcnp@yahoo.com>
To: "Pianotech" <pianotech@ptg.org>
Sent: August 13, 2003 1:46 PM
Subject: Re: Soundboard crown & carbon fiber & cellos


> Yes. And since it has been repeatedly stated by some
> on this list that the ribs alone support crown, with
> no help whatsoever from the rim or board, I do
> sincerely hope that they who have made this assertion
> will try carbon fiber ribs, or some other material
> with no compression set.
>      Thanks!
>      Thump


Keeping in mind that there are (and long have been) two methods of crowning
soundboards--let's try not to confuse the two systems.

What you are saying above applies only to rib-crowned soundboard systems.
In the case of the compression-crowned soundboard, the internal compression
of the panel (by creating a stress-interface against the ribs) both creates
and supports crown. Obviously, in this system the panel is "helping" to
support crown.

In neither case does the rim contribute to the long-term mainanaince of
crown.

Del