appraisal question another thonk?

[Dean May]

If you apply thin CA glue to the bass of the bridge it will go right into to
any voids. Lightly mist accelerator first. Wait a 2 minutes then apply the
glue. I've cured lots of bridge separations with this method- some that
showed no visible external signs. But you could watch the glue suck right
in.

Dean

-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of John Delacour
Sent: Saturday, August 26, 2006 3:44 PM
To: Pianotech List
Subject: Re: appraisal question another thonk?

At 9:37 am -0700 26/8/06, Bob Hull wrote:

>This B has a strange sound in the first 5 or 6 notes of the treble 
>strings and bridge.  The tone is weak, reminds me of a really cheap 
>sounding old baby grand, tone is unfocused, makes you think about 
>poor termination somewhere;  I would perhaps describe it like  a 
>recent post that mentioned a tenor "thonk".
>
>The  bridge glue joint in that area looks ok, bridge looks ok, there 
>is some downbearing...

Looks is looks and ain't always is.  To me this sounds like a parting 
of the end of the bridge from the soundboard and it would certainly 
not be visible.  My guess is that you could cure the problem if you 
were to drill a 4mm. hole through to the skirt of the bridge and the 
soundboard very close to the bridge proper and clamp the bridge to 
the board with a slotted bolt and nut (with suitable washers).  You 
might need one or two more bolts through the skirt.  Before you do 
that you can see whether this is indeed the problem by applying very 
firm pressure to the end of the bridge and the skirt with padded 
sticks and seeing if there is an improvement in the tone.

This job can be done very neatly and will have permanent effect until 
one fine day the piano is restrung, at which time the bridge can be 
reglued and the bolt holes plugged.


JD