[CAUT] Bechstein model B tuning stability

[Ed Sutton]

Fred-

The point of Dan Levitan's over-the-stretcher lever is not to "eliminate flagpoling." The point is to eliminate unintentional flagpoling. You are free to control flagpoling in all directions, with or witout rotational forces. 

In a standard tuning lever, whenever you apply rotational force, you are also applying a certain amount of tilting force, proportional to the "rise" of the handle from the pin in the block, in the direction you are pushing the handle to rotate the pin.  

In Dan's over-the-stretcher lever, there is no rise, so if you rotate, you only rotate. But you are also free to tilt the pin in any direction, intentionally, not accidentally. It's not at odds with your approach, it's a more controllable version of your approach.

Ed
  ----- Original Message ----- 
  From: Fred Sturm 
  To: caut at ptg.org 
  Sent: Sunday, October 18, 2009 12:45 PM
  Subject: Re: [CAUT] Bechstein model B tuning stability


  On Oct 17, 2009, at 3:53 PM, Jeannie Grassi wrote:


    Hi Fred, and anyone else,
    Can you take your description of downward and upward motion a step further?  I’ve been hearing conflicting descriptions of this recently in private communications.  What I’m asking is specifically….when the pitch needs to go up, do you lift up on the end of the tuning lever at the same time there is a slight rotation to sharpen?  And conversely, does one push down and rotate slightly flat?  I’ve had the opposite described and just want to get a sense of how most people interpret this deliberate flag-poling motion.  I’ve always used it the way I’ve described.  Have I been climbing up the wrong flagpole all these years????  :>)
    jeannie


  I can't speak for anybody else, but in my own practice, I make us of flagpoling consciously as a way to "compensate for" the combination of bearing friction and tuning pin twist. 
  Tuning pin twist varies depending on friction in the block, usually called torque. When there is high torque to overcome, the top of the pin twists a good bit before it moves as a whole in the block. This pulls considerably on the string. But how much the pitch changes before the pin begins to move is dependent on bearing friction. Usually, pitch moves before the pin actually rotates. So in that case, I flagpole the pin toward the string (push down on a grand, pull out on an upright), and I try to do so just enough so that when I feel the pin move in the block, I simultaneously hear the pitch begin to change (or see it on an ETD display). 
  I find that by doing this consciously and consistently, I have a much better idea at all times of exactly where the tuning pin is relative to where I want it to be. In the end, what matters is precisely how much and to what position you turn the pin. That's what leaves you in a stable condition. 
  What I aim for is to move both the pin and the string the precise amount necessary in the direction needed, no overshoot. I'm not saying it is always possible, but often it is very nearly possible. In fine tuning, I will often bear down on the hammer (assuming raising pitch) so that I feel the pin move a tiny bit and the pitch hasn't moved at all. Then I manipulate the hammer, flagpoling upward to pull the string across bearing points and see whether it has moved enough (or too much or not enough) by wiggling the hammer - essentially the method Steve Brady has written about and taught for many years. The idea here is to focus on the feel of the pin, and on moving it/nudging it the tiniest possible amount without the confusing feedback of pitch change. It also separates the movement of the pin and the movement of the string into two tiny controlled movements, which is a lot easier to keep track of.
  If there is a lot of friction, things change. In that case, I will often pull up on the lever while turning it, adding flagpoling to the inescapable twisting. Lowering pitch has a different feel, and with high friction I will usually press down to help move the string, with harder blows. 
  But the principle always remains the same: do the amount of flagpoling in the appropriate direction that will get as close as possible to having the pitch and the pin move in sync. Sometimes that means no flagpoling at all. I should add to all this that I assume a 12 o'clock position so that the flagpoling of the pin at a right angle to the lever (that happens because the lever is higher than the pin) doesn't enter the equation, and so that pulling up and pushing down has the maximum effect (is in line with the string). 
  Dan Levitan's invention more or less eliminates flagpoling altogether by putting the point where you are activating the lever in the same plane as the pin in the block. That is an entirely different concept, and one that is at odds with my own method. But it certainly might work well for others.

  Regards,
  Fred Sturm
  University of New Mexico
  fssturm at unm.edu









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