Steinway damper ringing problem

[llafargue]

I agree with Ed totally.  I always blamed it on our humidity here, but I
guess it's in other areas, too.  I always check tight parts first.
Under levers, guide rail, etc.  Also, I have found several B's and D's
with aliquot ringing and sympathetic high treble ringing in excess that
is difficult if not impossible to stop. Shifting and seating aliquot
segments usually works.  

Lance Lafargue, RPT
LAFARGUE PIANOS
New Orleans Chapter, PTG
985.72P.IANO
llafargue@charter.net
 

-----Original Message-----
From: caut-bounces@ptg.org [mailto:caut-bounces@ptg.org] On Behalf Of
A440A@aol.com
Sent: Tuesday, March 16, 2004 6:44 PM
To: caut@ptg.org
Subject: Steinway damper ringing problem

Alan writes: 
<< . I have noticed a few
newer S&S grands damping to be not as effective, in the bass
particularly.
On first blush I was guessing that the felt is the culprit, but I
haven't
been in the position to investigate these pianos.  >>

Greetings, 
   I have!   The new model Steinways present some baffling production 
characteristics  with the dampers. Combinations of these  can show up as
the 
aforementioned problems.  Here are some: 

1.  Pinning.  Steinway has a rich 160 year tradition of pinning
problems, and 
the new damper actions are no exception.  It is not uncommon to find a
one 
year old piano with 25% of the pinning overly tight.  In the
hammerflanges, it 
creates a heavy and unresponsive touch, (especially when coupled with
tight 
springs, and too much drop and let-off).  In the damper assembly, the
top-post 
pinning is often too tight, will make for slow damping.  This particular
pin 
doesn't see a lot of stress, so it doesn't loosen up much with use.  
2.  Damper wires.  For some reason, the last few years of production
have 
used wires that are really rough.  You can hear the noise from them when
you lift 
a damper by hand.  It sounds and feels like a file rubbing against the
guide 
bushing.  In several rooms at the university,  the new pianos are side
by side 
with 40-70 year old Steinways and the old pianos wire is dead silent as
it 
moves through the bushing.  Polishing them doesn't seem to help, either.

3.  Lateral pressure in the bushing.  It may be that the damper dept.
workers 
have to get a certain number of pianos traveled in a day and with a lot
of 
side pressure, it is easier to make things appear stable. However,  when

combined with the rough wires, excessive side-pressure will slow a
damper down, and 
if there is a little too much tension in the pinning, well, it all adds
up!   
In addition, the excessive pressure and rough wire will gradually wear 
sideways, and the trichord felt will gradually be distorted to one side
as the 
traveling goes to seed.  This creates a delayed fault, and becomes a
problem after 
several years of use. (Much like the nicks in the front rail pins
produce really 
loose key-bushings after a year or two).  

    I would check pinning first, then relieve the damper wires.  It is
also 
important to check the treble damper tray pivot block.  These are no
longer 
fitted snugly between the keybed and bottom of the belly rail structure.
If they 
were, they wouldn't so easily twist, but it isn't uncommon to find that
they 
have rotated on the single screw holding them in place. When this
happens, the 
tray moves sideways and ALL damper traveling is affected.  
   I have even found several pianos in which the screw was not given 
clearance in the pivot block, but rather, was threaded through the block
and into the 
back of the action cavity.  This destroyed the "clamping" effect of the
screw 
and simply locked the block on the screw-threads. In the first dry
season, the 
block was free to turn and no amount of tightening would resolve it.
The  
head of the screw was anchored agains the bottom of the hole in the
block and 
the only fix was to remove the block, drill the hole large enough for
the screw 
to pass through it freely, and re-install.  While you have the block
out, pay 
attention to how tight the tray pivot pin is in the hole,  sometimes
there is 
a problem there, too.  
   Slow dampers are just symptoms of other problems, and most
back-actions 
need a couple of hours time to get really right, if you are lucky.   
Regards,  
Ed Foote RPT 
http://www.uk-piano.org/edfoote/index.html
www.uk-piano.org/edfoote/well_tempered_piano.html
 
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