Center pin friction, yet again.

[Susan Kline]

At 11:21 AM 1/24/2006 -0500, Ed Foote wrote:
>I find a repinned flange has loosened up a lot from where I left it.  I
>learn from this, because I pencil the pin size under the hammer shank 
>boss, and
>the date.

That's a very good idea. That could be very useful.

In your list of different pinning opinions (so to speak), I find
myself on the firmer side, though not at the extreme end. It
helps that humidity is very consistent in Oregon, so I don't
need to leave a safety factor for muggy summers.

I think that when people pin for 5-7 swings, they sometimes don't allow for
a few factors: (1) as was stated, a little bit of hard playing, and two or
three swings will be added. Just grabbing the flange and vigorously pulling
the shank back and forth will demonstrate this. So if I pin for three
swings, it will become five or six in a matter of days. (A few Liszt
etudes ...) (2) The good concert pianos where pinning is important
enough that money is found for it usually get heavy use. We can pin
for supposedly "ideal" friction, and in three months, what are we
going to get? [too darned loose ... 14 swings?] (3) good tone requires some
firmness, as you say (4) if hammers are too loose, and rep springs aren't
adjusted to take it into account, you can feel the kick as the hammer
comes out of check, through the key. Sometimes you can even hear it. Having
the rep levers also getting looser from heavy wear doesn't help a bit. But
if you adjust the springs so that the hammers don't jerk nervously after
leaving check, the springs will be too weak for fast jack return.
(4) really loose hammer centers worsen checking problems, especially in
the tenor. Weakening the springs to improve checking wrecks repetition,
makes the action uneven, and in general the piano plays like a pig 
regulated it.
(5) There was the time I repinned a very worn old Steinway B action, and
I worried about the increased friction, because the downweight was
on the heavy side to begin with. The pianist, on the other hand, gushed
about how much easier the piano was to play, how much less fatigued she
got. I don't hear many people talking about it, but an uncontrollable
fly-away action can be more fatiguing than a controllable one with a
few more grams of down-weight. So I don't agree with the people who set
up a piano action with minimal friction in the centers, thinking
that they are going to get a nice light-playing piano. Just putting
protek or alcohol on all the centers, or installing new parts with
almost no friction, no matter that they don't have sideplay, isn't
going to correct for bad geometry.

Ed, thanks for your good posts. I save a lot of them.

Susan Kline