More cut-off bar questions

[Delwin D Fandrich]

----- Original Message -----
From: "David Love" <davidlovepianos@earthlink.net>
To: "Pianotech" <pianotech@ptg.org>
Sent: July 15, 2003 9:01 PM
Subject: More cut-off bar questions


> I'm looking at (or under) a Boes today and noticing that the cut-off bar
> goes from the straight side to the belly rail but does not contact the
> beams.  Previous posts on this topic have suggested the necessity of
> affixing the cutoff bar to the beams as well.  Is there any compelling
> reason to do it one way or t'other.
>
>
> David Love
> davidlovepianos@earthlink.net
>

The idea of a cutoff bar is to physically and acoustically cut off, or
shape, the soundboard. To do this most efficiently requires that the cutoff
bar be reasonably stiff and massive. Physically attaching the cutoff to the
belly braces both stiffens the bar and (by coupling to the braces)
increases the apparent mass of the bar. By floating the cutoff as you
describe simply decreases its efficiency somewhat.

Del