[pianotech] New string broke twice

[Joe Goss]

Hi,
Is there an extreme dog leg on that string?

Joe Goss BSMusEd MMusEd RPT
imatunr at srvinet.com
www.mothergoosetools.com
  ----- Original Message ----- 
  From: Noah Frere 
  To: pianotech at ptg.org 
  Sent: Tuesday, July 12, 2011 2:19 PM
  Subject: [pianotech] New string broke twice


  I epoxied a bridge for an Acrosonic #293752. String #33 was broken (the right string of G#2). I don't remember at this point if I had the broken string to measure, or if I ordered based on the left string specs. Ordered string from Schaff. It broke above the V-bar while bringing it up to pitch. I could feel too much tension before it was even a semitone away. Sure enough it snapped before it reached pitch. I spliced it - snapped again. 

  Schaff was kind enough to replace it at no charge. I figured it was a flawed string. Again, the same exact feeling and pop. Right at the point the string begins to coil on the pin. I could feel it coming. Probably should have looked more closely before popping it. The string was straight, which tells me it wasn't catching on anything. I can't imagine why the epoxied bridge cracks should effect it. I have installed dozens of strings, and don't feel like I did anything wrong. Could it be a whole batch of string is flawed? 

  Today I measured the left string, and it did read .001" smaller core diameter and .002" smaller copper diameter. The length of the winding looked good. I didn't think this is significant enough to break a string, but I'm not sure. (It is significant enough to give a poor unison though.) I tested the strings adjacent, lowering pitch and re-raising to see how tight they feel - they felt normal. 

  I'm thinking of ordering from a different company, being super careful while replacing, and seeing what happens. If it works normally, I could call Schaff and ask for a refund. If they refuse, no big deal. However, if this new string breaks even after being super careful, then I'm at a loss. I will order based on the left string measurements, naturally. 

  Has this happened to any of you?

  FYI the strings that broke - and yes I mic'd them before installing - were .040 core; .118 winding; hitch to winding 5 1/8"; winding length 30 3/4".   The new string will be the same lengths but .039 core and .116 winding. 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20110712/106738b8/attachment.htm>