Cracked Bridges - Continued

[Vanderhoofven]

Dear Jan,

A friend of me has helped me remove four bass bridges, so I will report on
his method.  First, go behind the piano and unscrew the three or four
screws that hold the bass bridge to the soundboard.  Then put the piano on
its back on a piano tilter.  Loosen all of the bass strings and get them
out of the way of your work.  Then use some very strong Ascetic acid, and
apply it liberally to the glue joint where the soundboard and the bridge
meet.  You may have to wait for quite a long time and keep applying more
Ascetic acid but the bridge will come off, usually with a minimum of damage
to the soundboard.

The Ascetic acid my friend used was very strong, (I think it was 36%
Ascetic Acid).  You may be able to get it from a photography supply store,
and I think that Ford piano supply used to sell it before they changed to
Beethoven piano supply.  

Now I have a question that I have wondered about for a long time?.  How do
you make sure that the new bridge will have the right amount of downbearing
before you restring it?  We had tried to duplicate the old bridge as
closely as possible and just hoped that it was right.  What is the best
method to make wure that the new bridge is correct?

Thanks!

David 


At 10:15 PM 9/22/97 -0400, you wrote:
>Dear List --
>
>Now we're having a nasty time getting the old bridge out.  We got the
>soundboard button screws out OK and we were hoping it would have been an
>easy matter to knock off the bridge/apron assembly from there.  It won't
>budge.  We would like to get it off in as much of a single piece as
>possible so that we may send it off to be duplicated (neither one of us
>has the shop capabilities to do the duplication job ourselves).  Does
>anyone have any great ideas on how to blast this thing off without
>blowing a big hole in the soundboard?

>Thank you in advance --
>
>ZR! RPT and Jano
>diskladame@provide.net and jano@provide.net



David A. Vanderhoofven, RPT
Joplin, Missouri, USA        
e-mail:  dkvander@clandjop.com

web page:  http://www.clandjop.com/~dkvander/
#pianotech page:  http://www.clandjop.com/~dkvander/ircpiano.html