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<P><FONT size=2><BR><FONT face="Comic Sans MS">If memory serves, the notion that
the bridge should not be "doglegged" comes from the philosophy holding that
sound needs to travel unimpeded back and forth throughout the interior of the
bridge. For more on this see Wm Braid White's book, <EM>Theory and Practice of
Pianoforte Building</EM>, 1906.<BR><BR>I believe it was also White that wrote
about the need to reduce the width of the bridge at the glue joint to allow the
surface of the soundboard to more freely "undulate."<BR><BR>Del<BR><BR></FONT>|
-----Original Message-----<BR>| From: pianotech-bounces@ptg.org<BR>| [<A
href="mailto:pianotech-bounces@ptg.org">mailto:pianotech-bounces@ptg.org</A>] On
Behalf Of Ron Nossaman<BR>| Sent: December 19, 2006 11:52 AM<BR>| To: Pianotech
List<BR>| Subject: Re: Bridge Doglegs, was: Spreadsheet info / Jason
Kanter<BR>|<BR>|<BR>| I'm not convinced that grain continuity along the
bridge<BR>| length is remotely a big deal. I build bridges with open ended<BR>|
laminations at the doglegs. (photo) It makes it easier to jig<BR>| up for a one
off bridge, and I can make whatever is called for<BR>| by the log progression of
speaking lengths. If there is any<BR>| tonal penalty for doing this, I sure
haven't been able to<BR>| detect it. This should be doable in production
too with few<BR>| problems.<BR>|<BR>|<BR>| > I am not entirely sure that
there might not be a good acoustical purpose<BR>| > served by minimizing the
dogleg. I am getting into dangerous territory<BR>| > here, since
I have no study to point to which would support this argument.<BR>| > There
must be some reason why the treble bridge is commonly undercut to<BR>| > make
the gluing surface with the soundboard a smooth(er) curve. I'm<BR>| >
thinking that the more the long bridge snakes along the soundboard, the<BR>|
> more its capacity to transfer its energy to the board is inhibited.
(Flame<BR>| > suit on. Go for it!)<BR>| ><BR>| > Frank
Emerson<BR>|<BR>| I undercut the treble section and front of the treble
dogleg<BR>| to get the bridge footprint as far away from the belly rail as<BR>|
I practically can. Other than that, I haven't been able to<BR>| detect any
indication that the soundboard cares one way or the<BR>| other if the footprint
doglegs at the break. Just my<BR>| experience. Anyone requiring absolute proof
is going to have<BR>| to generate their own.<BR>|<BR>| Ron N<BR>|
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