tuning instability on new Baldwin SD10

[Don Mannino]

Paul,

- Inspect the hitch pin area very carefully, in case the roll pin is not driven in far enough.
- Inspect the bridge pins very carefully, and look for issues with the bridge top or pins, elongation of the pin holes, etc.
- Check the string coils on the tuning pins, and look for a string pulling out of the pin because the becket length is too short.
- I haven't looked at a new SD-10 in a long time to see if the design of the termination bars has changed, but check carefully around the capo for something which might allow the strings to dig in.  Or, look for an agraffe that is cracked and is lifting (if it is it in agraffes area - I think the 5th octave spans the treble break).

20c drop repeatedly indicates a problem, but if that was only one time and the other re-tunes have only been small changes of a few cents, then do some light string seating work (bridge, counter-bearings, etc).  Also, seat the string coils on the tuning pins to be sure they aren't too high or too low.

Don't drive the tuning pins down unless the pins are obviously loose.

Good luck!

Don Mannino
  ----- Original Message ----- 
  From: Paul Mulik 
  To: pianotech at ptg.org 
  Sent: Thursday, December 27, 2007 6:01 AM
  Subject: tuning instability on new Baldwin SD10


  Hello list,

  One month ago my church bought a new Baldwin SD10.  I installed a DC the day after it was delivered (2 tanks, 3 rods), tuned it a few days later, and tuned it again a couple of weeks after that.  

  I'm having trouble with a few of the unisons in the fifth octave, there are 3 or 4 strings that just will not stay in tune.  I keep retuning them and they sound fine for a while,  but then a few days later they'll be 20 cents flat.  The tuning pins do not feel loose, and I've tuned other large grands with no difficulties, so I don't think the problem lies in my tuning technique (though I could be wrong -- wouldn't be the first time!)  I have not tried driving the pins further into the pinblock; it seems to me this shouldn't be necessary on a new piano, but again, I could be wrong.

  Any suggestions?

  Paul Mulik
  Joplin, MO
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