Back to coil tapping, momentarily

[Roger Jolly]

Greetings Jim,
              Nice post, and not overly suprising results, however the
start of this thread was tuning stability. Bridge vs coils, and I agree
with every thing you and Don have posted on the subject.
 Now comes the BUT. We know that very little shock, is needed on a tuning
pin to dramatically alter pitch, the impact coil tighteners sends one heck
of a shock wave through out the whole termination system, and that is why
it works so efficiently at tightening the coils and equalising tension. If
you are looking at long term stability, it is also very important to check
the angle of deflection of the string as it leaves the tuning pin, as well
as the height of the string from the plate. The coil should not cover the
becket hole on the open side, and in a perfect world, the becket should be
just above the point that the string leaves the pin.
 If the pin is sitting too high from the plate, the impact devices can and
will often, deflect the string as it leaves the pin and actually reduce
stability.
Therefore it is important to ensure that the bottom of the coil is close to
1/8" from the plate.
 My original contention was that the bridge/string condition, along with
plate bolts, had a more significant effect unless the coils were obviously
bad.
Regards Roger


 Some times the impact devices can deflect the string as it leaves the pin
in such a manner that it can be counter productive to tuning stability. 
>
>3. Last night I increased the page by 5  cents (A440 +5cents) and tuned the
>thing for the seventh time.  It sat all day without being touched and I just
>went over and tapped the coils again. This time there was a spread of from 10
>cents(F3) to 23 cents(A6) almost evenly divided/graduated through the same 8
>measured notes.
>
>  Based on these measurements I would say that tapping definitely changes
>tensions in string length (and should be a good adjunct to tuning stability?)
>  So there it is, use it as you will.
>Jim Bryant (FL) 
>
> 
>
>
Roger Jolly
Balwin Yamaha Piano Centres.
Saskatoon/Regina.
Canada.