Young Chang lyre supports buzzing

[Don Mannino]

Dave,

 

No, the downward force has not been an issue for me.  If you really want to
analyze it, you will find that the box has a sort of rotational force on it
that is pretty much the opposite of the force from using the pedals.  This
causes binding with the lyre posts, so the glue joints are not stressed
badly.  Using the pedals puts much more downward force on the box.  If the
glue joints are going to fail, any rocking movement of the lyre is what
works the joints loose fastest (especially at the top).  With the lyre
pre-loaded forward, it rocks less, and the joints should hold up better.

 

Don Mannino

 

From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of Porritt, David
Sent: Friday, July 11, 2008 9:55 AM
To: Pianotech List
Subject: RE: Young Chang lyre supports buzzing

 

Don:

 

When you move the lyre brace mounting closer to the lyre you're adding force
forward, but actually even more force downward.  If these lyre assemblies
are not constructed of pretty hard wood and good glue do you think this
extra downward force would accelerate wear?

 

dp

 

David M. Porritt, RPT

dporritt at smu.edu

 

From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of Don Mannino
Sent: Friday, July 11, 2008 10:47 AM
To: Pianotech List
Subject: Re: Young Chang lyre supports buzzing

 

Bruce,

 

It works well to re-locate the top of the lyre support.  The rods should
really be pushing the lyre forward a little anyway, so by re-locating the
tops of the supports slightly closer to the lyre, you "load" the system for
best stability and strength.  It also stops the rods from buzzing.

 

It's also easy to do, as the wood on the bottom of the keybed is pretty
soft.  Just remove the screws, drop the support rod down and plug the holes.
Then raise the rod back into position, and push the top of the support rod
towards the lyre, and drive the screws back in at the new location.

 

While you're there, check that the pedal lyre isn't coming apart where the
posts meet the box.  This could be the reason for the support rods
loosening.  Fixing the lyre might also tighten the rods back up in the
original location.

 

Don Mannino

 

----- Original Message ----- 

From: Bruce Dornfeld <mailto:bdornfeld at earthlink.net>  

To: pianotech <mailto:pianotech at ptg.org>  

Sent: Thursday, July 10, 2008 9:29 PM

Subject: Young Chang lyre supports buzzing

 

I have a number of grand pianos built by Young Chang that I service that
have the same trouble.  The lyre support brackets vibrate or buzz with some
frequencies when the piano is played.  When all of the screws are tightened,
there is too much play in the hinge.  This is most often causing noise at
the top of the lyre support, but sometimes at the bottom too.  Sympathetic
vibrations are always a pain, but I do not know how to fix these. 

 

This week, I removed a pair of them to repair,  First, I tried hitting the
pin with a ball peen hammer with the other end on an anvil, but it only made
it flatter outside of the hinge area.  Previously, I have tried wrapping
some yarn around it, but it did not last.  I have considered squeezing the
bracket around the pin, but is looks like cast metal and I am afraid it
might just break.

 

There are tons of Young Changs out there.  What are you all doing to keep
the lyre support brackets from vibrating along with the music?  I can't be
the only one having trouble with these!  Help me!  Please! 

 

 

Bruce Dornfeld, RPT

bdornfeld at earthlink.net

North Shore Chapter

-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20080711/13ac76c8/attachment.html