Dealing with bridge damage.

[Andrew and Rebeca Anderson]

Ed,
This might be an acceptable alternative to pulling the plate and 
re-capping it.  The string I CA treated the first time around did not 
make it self obvious at the next tuning so it is holding as a 
temporary repair.  I did notice a loss of zing on the couple I 
treated but that was in a short period of time and probably the CA 
hadn't fully set.  I take notes on all my work so I'll go back with 
the notes and check into those strings specifically next 
service.  I'm not enthusiastic about it though...I've done wood work, 
this won't  be fun doing.  I guess a regular high bond wood glue will 
do the job of bonding in the new wood and a file and razor to level 
everything again without having to de-string everything and pull all 
the bridge pins for a plane.

Andrew Anderson

At 12:31 PM 4/25/2006, you wrote:
>There is a repair technic used in woodblock printing: cut out the 
>mistake with a small V gouge, then cut a sliver of wood with the 
>same gouge, matching the grain orientation, and glue it in the 
>groove, then plane the top level to the surface.
>If you pull the pins, you may be able to cut out the string dents 
>and replace them with new wood and cut new edges to the 
>notch.   Little V gouges can be gotten in art supply stores.
>Ed Sutton
>
>
>-----Original Message-----
>From: Andrew and Rebeca Anderson
>Sent: Apr 25, 2006 1:09 PM
>To: Pianotech List
>Subject: Dealing with bridge damage.
>
>I've been maintaining a 4 year old D for this concert season at the 
>local community college.  Almost every service I end up working on 
>the treble bridge.  I've ultra-thin CA-treated the bridge pins to 
>great benefit.  Closer investigation revealed that the persistent 
>culprits had been victims of savage "string-seating".  Some were 
>beating so wildly as to be practically un-tunable.  In desperation 
>(concert in an hour) I treated one with gap filling CA glue.  It 
>worked, but not without a price.  I've been planning to fix this 
>bridge damage with a hard epoxy, selection process still ongoing 
>(advice welcome and hereby solicited).  The string stopped beating 
>but lost a little of its "sizzle."  I'm guessing that the CA isn't 
>hard enough (or hadn't fully set).  Mind you, with the strings 
>working in unison, I have more power after the treatment than 
>before.  I've since done a few more that were obviously 
>damaged.  I'm watching to see how they do long-term.  I don't see 
>how I can re-cap the bridge with the plate still in.  Has anyone 
>else tried to do this?
>
>There is a little beating throughout this section and it does seem 
>to be impedance related (heavy object in contact with bridge 
>ameliorates it).  Probably why there is so much bridge damage--an in 
>determined string-seating by a predecessor.  I am planning to do 
>some work with that after I get approval to hang brass under the 
>bridge.  We have also discussed a "treble tone resonator" (Pianotek 
>belly brace) for this as well.  I have thought that placing a heavy 
>weight against the belly rail here might be a test that could 
>confirm whether or not this part would be a useful addition.  They 
>do want some audible demonstration of the advantage of the expensive 
>part.  There is a lack of sustain and power in the fifth and lower 
>sixth octaves.
>
>Overall the faculty is ecstatic with the improvement in the piano 
>and I'm getting affectionate feedback that I must be nitpicking a 
>little.  I guess it is only a Steinway. :-X
>
>Andrew Anderson

-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20060425/5f4d5a70/attachment-0001.html