Young Chang tuning instability

[J Patrick Draine]

Lots of good advice already.
1) Humidity & temperature control, as complete as possible (as Dean recommends).
2) Voicing. Rock hard hammers knock a tuning out faster than a
properly prepared hammer.
3) Multiple passes. One pass tunings are seldom very stable.
4) As Jon said, hammer technique. You may well be setting the pin
properly, but leaving the tuning pin segment at a different tension
level than the main string segment. This can be caused by excess
friction at the pressure bar &/or understring felt. I recall S&S tech
reps recommending deflecting the string with a hammer shank to help
overcome that friction to stabilize the differing tension levels.
Obviously time consuming, but makes sense for concert prep.
5) Experience. "new" technicians run into problems like this more than
the old hands, but it does happen to those of us who've been at this
for decades. Relax (hey it's a holiday!), and implement points 1
through 4 in your everyday service, charge appropriately, and you will
be pleasantly surprised.
Thanks to all, time to get the house in order for the big crowd,
Patrick

On Nov 21, 2007 9:21 PM,  <brittanykirk272 at comcast.net> wrote:
>
> I have regularly tuned a Young Chang PF-250 for about a year, and it sounds
> horrible every time I come back for another tune.  In the tenor section, one
> note might be +15 cents, while the one next to it is -15.   Unisons are
> completely unacceptable.  Bass section and high treble seem to be okay.
>
> The person who plays this piano is a "Horowitz", plays very hard, but I
> still think the stability could be better.  Plate bolts are tight, tuning
> pins have sufficient torque, I have seated strings, and I pound the heck out
> of it every time I tune.
>
> Ideas?  Can not enough downbearing cause tuning instability?
>
> Ms. Kirk.