Sluggish keys

[Brian Trout]

Hi Jere,

You didn't mention if this is a grand or a vertical, but the reasoning isn't
all that different between the two.

As you press down a key, the action begins it's cycle to move the hammer
towards the key.  As the hammer gets to around the spot where it's 1/3 - 1/2
of the way along in it's trip toward the string, some part of the action
will (normally) then begin to move the associated damper assembly away from
the string, (the back of the key for a grand, and the spoon on the wippen of
the vertical.)  On the grand, the weight of the damper and associated
assembly is then added to the force needed to move the key through it's
cycle.  On the upright, it's a matter of the tension of the damper lever
spring which needs to be overcome.

When you press down the damper pedal on the grand, you no longer have to
lift the individual damper assemblies by the force applied at the key(s)
because the dampers and their associated assemblies are all being held up by
the pedal.  Similarly, on the upright, the pedal assemblies will hold those
damper levers out of the way of the spoons and remove the additional force
normally associated with those springs.

On the return of the hammer and damper assemblies, the weight of the damper
assembly (grand) or the force applied by the damper lever spring (vertical)
are applying additional force to return the action to it's rest position for
1/2 to 2/3 of the return part of the cycle, that is unless the damper pedal
is engaged.  These forces are significant and need to be taken into
consideration as they pertain to regulation and the feel of a piano.

That being said, the action should be able to return to it's normal rest
position fairly quickly even with the damper pedal engaged.  It might be
good to check some of the areas throughout the action that normally cause
frictional problems.  Many times,  I have found similar situations where key
easing was called for.  Other times, repinning of centers was called for.
On still other occasions, center pin lube has done a good job.  Another
thing I've seen on some of the newer Samick (and similar) products is where
there were so many weights in the key, apparently to lighten the touch in
the bass, that the whole action would rebound after returning to it's rest
position, far enough to actually lift the damper again sort of resembling
bleeding dampers.  But that's another topic...

There's so much stuff that goes on, and it's all related.  One thing affects
another.

I don't know if that was what you wanted to know, or if I said it so well,
but I hope it will help at least a little.

Good luck,

Brian Trout
Quarryville, PA
btrout@desupernet.net