[pianotech] Thanks to JD

[William Truitt]

To the list:

 

A few weeks or so ago JD sent in some pictures and a description of removing
a bridge cap using a thin  knife and some liquid to attach the glue joint (
I can't remember if it was vinegar or denatured alcohol, or what)

 

Anyway, yesterday I tried his technique on the treble bridge of a 1909
Steinway A2.  At the low end of the tenor, the cap was kind enough to be
beginning to lift away on its own.  So I worked my tapered knife into there
and took an eyedropper and kept squirting denatured alcohol into the opening
and exposed joint.  I kept working the knife back and forth down along the
bridge length, pausing to add alcohol periodically.  

 

I had the entire cap off in about 20 minutes, leaving the root pretty much
undisturbed - it separated at the glue joint along the entire length.  The
capping piece was still intact.

 

There is much to like about this system.  It has been my experience that,
because of the irregular shape of the treble bridge, it is difficult to be
always consistent in planing off the old cap, whether by hand or machine.
This method leaves the glue joint line essentially undisturbed if you are
careful enough.  I will be plugging all the bridge pin holes prior  to
recapping.

 

I did something similar removing the bridge from the soundboard on a Mason &
Hamlin A a few months ago.  After drilling out the dowels going through the
soundboard into the bridge, I started breaking the glue joint at the tenor
end with a thin knife and denatured alcohol, working it back and forth.  In
this case I was using thicker wedges further from the intact glue line to
add pressure as I worked it with the alcohol and a knife.  And, once I got
far enough down the length of the bridge, I was taking a rubber mallet and
judiciously tapping down on the top of the bridge on the other side past my
wedges.  Careful tapping, along with the alcohol, the knife, and the wedges;
allowed me to get the bridge off pretty cleanly without damaging the bottom
of the bridge, and without tearing out too much of the softer spruce in the
panel.

 

A hearty thanks to you JD, for sharing your wisdom - to my benefit!

 

Will Truitt

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