[pianotech] Won't Stay in Tune

[Stephen Grattan]

Hi Noah,

Is the coil unwinding- pulling the becket out of the tuning pin hole?
 
Steve Grattan
Lost Chord Clinic




________________________________
From: Noah Frere <noahfrere at gmail.com>
To: pianotech at ptg.org
Sent: Wed, December 5, 2012 4:16:07 PM
Subject: [pianotech] Won't Stay in Tune

I just restrung a 1908 Whitney 3/4 plate tall Upright, with new bridge pins 
epoxied in using a syringe, ad 4/0 tuning pins. The pins are tight. I repeat, 
the middle string on F#6 has a TIGHT tuning pin, tight bridge pins, and a tight 
hitch pin. The string wraps around and comes up the right side as the right 
string. 


Sounds good, right? No - that note (and the center string of A#7) will not stay 
in tune for even 4 seconds! You can just hear it drop as you strike the string, 
like a miracle (or the opposite thereof.) The other notes, including the outside 
strings of F#6 and A#7 are fine. 


The only anomaly I am aware of is a split in the v-bar, which is, it turns out, 
made of wood. (There is a brass rod over the wood for the string termination.) 
AND the split is under the note. However, the split is long and deeply angled, 
as can be seen in the photo, and is not centered precisely under the offending 
string. Not that it needs to be. 


My best guess is that the split is continuing to spread under the strain of the 
string tension, and that the exact point of spread is under the center string of 
F#6. However, this doesn't explain the same problem on A#7. 


I was aware of the split before restringing, however it was so perfect looking, 
I thought it had to be part of the design. Besides, it seems to me that the 
split should eventually stop spreading (if that is what is happening) and settle 
on a place. But I have pulled up F#6 to pitch half a dozen times and it keeps 
dropping. 2 times ago it was at 33 cents below F6, but the last time it was 
right at F6. Somehow it is not effecting the right string. 


Any ideas? The photo is from slightly below, so you can see the overhang of the 
split. The split looks a little wider than it really is because of the overhang. 
I am keeping a careful eye on it to see if it widens. By the way, you can't see 
in the photo but the split continues down at that angle to the other side of the 
v-bar on the left. The center of the split is between the left string of F#6 and 
the right string of F6. Also, there are 2 more splits of the same type further 
on down the bass side of the v-bar, which strengthens my opinion that it is 
designed thus. There is no sign that the splits were glued together at any 
point. It's just that the v-bar is so long that it necessitated 3 sections 
during its construction.

Another idea is that the string is flawed, but then I would think it would turn 
up in the right side of the unison as well. 


I am pulling it much sharper than F#6 now to see how that effects it. Maybe it 
will break and a new one will solve the problem.
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