bridge caps and bearing

PHIL SLOFFER, MA067 855-1244 PSLOFFER@ucs.indiana.edu
Sat, 24 Dec 1994 08:11:52 +0000 (EWT)


What follows are some thoughts I have which I sort of put
together as a result of lots of questions to many people over a
long period of time.  Forgive me if I say anything wrong and
please feel free to correct any errors you may feel I have made.


>>>>>>>>>>>>Why should bridges have caps anyway?

Well bridges don't necessarily need caps.

It depends how bearing is set.

In both Steinway and Baldwin the plate is set to a "correct"
height so that action regulation will be consistent.  The bearing
is set later.

Baldwin sets bearing by using accu-just hitch pins where the wire
is moved up or down the hitch pin to get the correct bearing.

However with Steinway the bearing is set by planing the bridge
cap down to the proper height.  If you were to use a bridge
without a cap this might be a very difficult job especially if
the bridge had laminations with the grain going in both
directions.

Now as far as I know it makes no difference if the bridge in fact
has a cap or not.  What I think is a more important question has
to do with bearing.  If you replace a sound board then this
assumes that bearing is improved so my question is really about
those situations where the old sound board is used.

I know that some technicians will lower plates to get better
bearing even if the sound board has little or no crown.  I think
this is wrong.  I say leave the plate right where it is.  Then
the action will regulate OK.  Any improvement in sound gained
from lowering the plate will not last if the sound board is bad
anyway.  Put another way, if the old board sounds bad and it is
decided to leave it in place then don't make other things worse
by lowering the plate and making it impossible to regulate the
action.

The bearing is only right twice a year.  Once in the fall when
the board is coming down and once in the spring when the board is
going up.  The rest of the time it is only close.

Hope all of you have a Merry Christmas

Phil Sloffer


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