Hypothetically, if there were no friction then any change in the first segment would be immediately transmitted to all the other sections and there would be no differential. That's what happens when you merely pull on two ends of a string. And that's how I was thinking about it when I wrote this up which is incorrect in the real world. Of course there is friction and so there will be a temporary differential in segment tension until friction is overcome and those sections equalize. It doesn't really change the point of the technique which I am describing and which, during the demonstration, I believe most people understood. That is to raise the first segment tension no higher than is necessary to achieve the target in the speaking length without overshooting and having to drop things back through the friction points in order to get the pitch to settle at the target. The need to first overcome friction in one direction and then to have to overcome friction again in the opposite direction in order to be sure that things are stable is what costs time and can compromise stability (in my experience). If you can manipulate things such that you only have to be concerned with friction in one direction, you will be better off, I think. The problem and the time lost can be more pronounced on pianos with greater rendering problems, i.e., more friction, as you might imagine, and you end up chasing the pitch back and forth trying to determine whether friction has been adequately dealt with. The technique described is one of counter pressure on the pin in order to achieve that. David Love www.davidlovepianos.com For my own edification and creating a hypothetical situation: If there were zero friction at all bearing points, do the physics describe still show the first segment's tension will initially, in some degree, exceed the desired overall tension in the end? Keith=
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