[pianotech] Totally glueless

[David Love]

Seems there are two separate questions:  one of efficient and permanent
coupling of the bridge to the board, the other is the mechanics of the how
the sound is transmitted.  Given a reasonably tight coupling of the bridge
to the soundboard with screws the acoustics would seemingly not suffer, at
least not audibly and not as long as the joint remained tight: as the bridge
moves so does the board.  Whether there is, without the benefit of a rock
solid glue joint, some even fractional movement (friction) in which some of
the energy at some frequency(ies) might not be dissipated in the form of
heat is for more refined measuring devices than our ears will surely
deliver.  That we aren't able to discern the loss with our ears doesn't mean
there may not be some.  Some answers are complicated, especially those that
lead to other questions, and I don't think denigrating legitimate inquiries
is a very good path to knowledge.  Needless to say, it's best to glue the
bridge to the board.    

David Love
www.davidlovepianos.com


-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of Ed Foote
Sent: Thursday, January 31, 2013 6:06 AM
To: pianotech at ptg.org
Subject: Re: [pianotech] Totally glueless

Ron writes:
People have an absolute genius for complicating anything and everything and
feel compelled to invent detailed explanations whether they have any facts
or logic to work with or not. It's intuitive, instinctive, and fundamentally
irrational. It's also nearly universal. "I've heard", "I was taught", "I
believe", "it's obvious", "simply", and "stands to reason" are the enemies.
Innate contradictions like the glue joint blocking sound, while a loose
joint not passing vibrations because there was no glue with the screws,
should be questioned.>>

  Ok,  a question, then.  Do you glue your bridges to the soundboard, and if
so, why?  I don't think a pair of screws couples the bridge adequately to
the soundboard, either mechanically or acoustically, but if there are
reasons why that coupling isn't worth questions, I would love to hear them.
Regards,

Ed Foote RPT
http://www.piano-tuners.org/edfoote/well_tempered_piano.html