Whacking

[romanop@attglobal.net]

In the PTG tuning exam, stability is checked by dropping an eight ounce
weight from six inches above the key and then checking to see that the pitch
has not changed. It is a considerable "whack".

Phil Romano
Myrtle Beach, SC


----- Original Message -----
From: "David Ilvedson" <ilvey@jps.net>
To: "pianotech" <pianotech@ptg.org>
Sent: Sunday, February 11, 2001 9:17 PM
Subject: Re: Whacking


> The PTG Tuning test has a technique to test the stability of the unison
portion of the test.  Maybe someone can post that exact info.  It is not
whacking in any way...Tuning stability is a combination of good hammer
technique and an adequate force to insure that a portion of the string
segments isn't excessively different than other segments.  Equalizing of the
segments is apparently not possible...Hitting the keys as hard as you can
until the note won't drift means a total lack of hammer technique.  I do not
whack anymore and my tunings stand up to concertos...The archives have lots
of stuff on this subject.
>
> David I.
>
> *********** REPLY SEPARATOR  ***********
>
> On 2/11/01 at 8:18 PM Yardarm103669107@AOL.COM wrote:
>
> >Bill:
> >While the pin might be very stable, the segments of string from the
tuning
> >pin on out to the waste length are under less and less tension if the
> >pitch
> >is being changed upward; the reverse is true in pitch lowering. The
string
> >system is unstable until an equalizing force is used to attempt to
> >overcome
> >friction at terminations and get the tension to equalize. I personally
> >doubt
> >that a string system left unaltered is stable enough to leave for very
> >long.
> >On the other hand, a stiff blow which is allowed to linger rather than
> >stacato damped will go a long distance in stabilizing the string system.
> >Overhard blows can indeed destabilize the system in the reverse
direction.
> >
> >A good test of this phenomenon is to try this. The next time you have to
> >raise the pitch on a piano more than 20 cents, pick a string in the
middle
> >register and after pulling it up to where you want, take a brass punch
and
> >give the waste length of string on the other side of the bridge a tap in
> >the
> >opposite direction of the bridge pin, i.e. as if you were unseating the
> >string; you will immediately notice a drop in pitch in the singing length
> >as
> >tension is released around the bridge. If you did not give the string a
> >stiff
> >blow to equalize out tension, then that residual unequal tension would
> >gradually detune the piano. More thoughts? Is this clear? Again, I'm not
> >advocating damaging blows (either to the piano or to self).
> >PR-J
>
>
>