Una corda and double damper lift

[Owen Greyling]

Hi Paul,

Remove the stack from the action, and replace the keyframe with the keys in
the action cavity. Don't force the back of the keys under the underlevers,
but stop with the keys just in front of the underlevers, and check the
spacing of the back of the keys in relation to the levers..both at rest, and
in the shift position.
You may have to space the first eight underlevers slightly more to the
right. Pay attention to the keys that are operating correctly, as this will
give you the best guidelines as to what spacing is correct. This will
involve removing the dampers and rebending of the wires. Before you commit
to that approach however, you may be able to get away with planning the
width of the back of the key and end felt slightly, to create enough
clearance when the shift pedal is engaged. 

Before you do any of this, make sure that the action shift is operating
correctly in relation to the hammers and strings.

Good luck, and prepare to be a hero.

Owen

   

-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of paul bruesch
Sent: Saturday, May 24, 2008 5:36 PM
To: Pianotech List
Subject: Una corda and double damper lift

A client has a Young Chang TG-150, mfg in 2000. When I press the shift
pedal, it doesn't go down very far, and the action does not shift far
enough to play only two strings. I adjusted it so that it would shift
farther, but then the dampers of the wound bichords to the right of
the break (there are about eight such notes) would lift in pairs...
for example, playing D3 with the shift pedal down results in dampers
for D3 and D#3 being raised. This only happens on those eight or so
notes, not in the plain wire treble, nor in the wound bichords left of
the break.

Any ideas?
Thanks,
Paul Bruesch
Stillwater, MN