Esteemed list
I have taken my time following this up as I ponder
what attitude to take. For new readers...to review....
bridge is lower on speaking side then backscale side
by as much as 20 thou. over much of this new D
Steinway.. including the bass bridge. The result is
strings that will not stay seated, and various buzzing
off the backscale. It is severe enough in at least one
place the back of the bridge is highenough that there
is no pressure on the backscale plate before the hitch
pin and the string will buzz on the plate unless held
down to the plate or muted.
From previous posts I understand bridges do
not roll so much as soundboards in front of the
bridges may collapse. Also it was suggested by at
least one person that the piano was built this way.
I have a response from Stienway, and have
respectfuly taken off the name of the person
writing for the moment. They are coming from NY
to see this piano and in light of the response
I hope for more feedback. They obviously wish to
manage the problem and leave it alone. I can not
see strings staying seated in its current condition.
String seating and hammer mating is at present, in
my opinion, a waste of time.
Here it is.........
-------------------------------------------------
Hello David,
First, thank you for your very complete letter. Your
comments are very helpful in trying to assess any
possible problems with this piano.
As to the excess glue, you are correct that this is
simply glue squeeze-out that should have been cleaned
up in the manufacturing of the piano.
It is sometimes difficult to see this at the belly
rail but, as you have done, should be removed to
prevent possible buzzes in the future.
Concerning the bridge/downbearing, let's keep an eye
on this if the buzzes have been eliminated for the
time being. While it presents a situation to
keep an eye on, I do not want to make an immediate
pronouncement that there is something wrong there. The
primary thing that manufacturers look for is
the total composite bearing on the front and back
combined. This should, of course, be a positive
bearing. Theoretically, there should be positive front
and back bearing. However, pianos seldom conform to
the theoretically correct. I have taken many bearing
measurements - on both good sounding and
not-so-good sounding pianos. Some of the best sounding
pianos have exhibited the measurements you describe
below while some of the lesser sounding pianos
are textbook perfect. The downward forces of the
strings over the bridges (anywhere from 800 - 1100 lbs
of force) cause each piano to develop its own
unique shape. Sometimes that "settling" can be
measured to exhibit what we technicians commonly cause
bridge roll. That in itself is not a great cause
for concern but rather a sign that we need to monitor
this in case tonal issues arise consistently with a
piano.
In my experience, seating and leveling the strings,
hammer filing, voicing meticulously, hammer spacing,
and making sure the bridge pins are seated in
the bridges alleviate any tonal problems 98% of the
time. You MAY have one of the "2% pianos" there but
let's wait and see if problems develop again
before we determine a course of action.
Again, thanks for your very detailed and thoughtful
note. And please call or contact me if I can be of
service on any issues or questions you have.
----------------------------------------------------
Some of my Original Letter to Stienway........
-------------------------------------------------
Hello
Dave Renaud here, Ottawa-Gatineau, Canada.
One of my clients is the Quebec Conservatory in
Gatineau Quebec.
They have a new D you are likely aware of. It
was in ......cut...............
I have a few observations that should be
investigated.
Minor...... There were very large 2-3 inch long
shards of glue where the soundboard meets the belly
rail. Some of these thin shards from oozing glue
(I saved some, could take a pic.), were lightly
touching/buzzing against the board. I cleaned this up,
It eliminated some buzzes and did take time to
troubleshoot.........when all else was eliminated, I
thought it had to be the glue joint along the rim.
Major...... The bearing on the back of the bridges
is high, the bearing on the front(speaking side)
much lower. As much as 20 at the back and 0 at the
front. This is all over, on both the treble , and bass
bridge. I was motivated to measure because a buzz on
the backscale could not be eliminated without pushing
the string down on the backsacle plate. This string
would not seat on the plate due 0 bearing over the
plate, This lead be to wonder if Perhaps the back of
the bridge was high. It is, and the front is
low, string travelling downhill to the speaking
length.
These measurements were made with a Lowell gauge.
I followed up by having xxxx from xxx measure with a
bubble gauge. He had negative measuments on the bridge
cap angle all over the piano as much as negative 18 in
places. I then had xxxxx look at it and confirm the
same thing.
The strings should travel "uphill" to its
termination point at the speaking length.
They are travelling downhill to the speaking length.
Marcel came down from Quebec city, and spent a day
seating and mating strings, did a wonderful job, and
the piano was much better.
With the negative slop to the bridge nothing will
stay seated for long.
What believe has happened with this piano is
technicians arriving for a day, with a program
in mind to treat normal problems. Indeed, they find
strings that need seating, and hammers that need
mating....normal.....and proceed to fix it.
But on this piano, the poor seating, and string
mating is NOT because it was neglected, or not
maintained properly, and not because needs proper
concert service. We can do that. It is a recurring
symptom of the negative bridge cap angle.
The opinion that I am hearing suggested from techs
is the soundboard at the front of the bridge may have
collapsed somewhat. Hmmm...that belly rail that
should supports the crown and all those oozing glue
shards at that very joint. Could this mean something
related. What does those shards suggest in the
manufacturing process. Just too much glue? not
securely glued down at the belly normally? Just not
cleaned up? Just thinking out loud ...any thoughts
here.
If I am missing something here I am very
interested in understanding how this can be.
Your thoughts, observations, and suggested solutions
will be of great interest to me.
At this point I believe I have observe and
diagnosed
something everyone else has missed. Not that others
were in any way delinquent, they did fine fine
work, but were I think on a schedule, a program to
follow, and seeing the symptoms went straight to work
without sufficient "why is this." I happen to spent a
great deal of time in front of this instrument
tuning and pondering over recurring buzzes that
motivated me to look to the bridges,and check those
glue joints.
I hope this has been helpful
If I could make further measument charts, but I
think you see what is here.
If I can be of help, please ask away.
David Renaud
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