AB Chase Concert Grand

[Delwin D Fandrich]

> -----Original Message-----
> From: pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org]On
> Behalf Of Dean May
> Sent: April 05, 2004 7:14 AM
> To: Pianotech
> Subject: RE: AB Chase Concert Grand
>
>
> >From a structural standpoint, the beams go in the direction of
> the loading.
> Think about how the strings are wanting to fold up the piano. That is what
> the beams are resisting. So running a beam transverse to that direction of
> loading will have negligible effect on strength. It would make the overall
> frame more rigid, but it doesn't really need more rigidity in that
> direction.
>


This is true only if there is some load coupling mechanism between the plate
and the bellyrail and/or braces. (As with the Steinway plate horn.)
Otherwise the belly of the grand is not load-bearing.

It either case it is best if the bellybraces are spread across the bellyrail
to stabilize an otherwise rather floppy structure.

Del