OK if of course stretching is not the only reason for the string to go out of tune it still is the most important. I come back to the basis : On many instruments the solicitation of plain wire is beginning very low. Theses strings are loosing their tension very slowly, so they take a long time to be stable. The experiments and computations say : A string A4 if solicited at 40% of the practical breaking point (the data of the string maker being lessened 25% for the computations) will lost (naturally) 1.13% of its initial tension after 5 years 442 Hz >> 439.5 If the solicitation is 60 % it will loose 7.4% tension only in 5 years. 442 Hz >> 425.5 We aim for a good state of stabilization of the strings, where the rapid plastic deformation under load have been absorbed. At the same time the properties of the metal have been modified leaving us with a more resisting string. The method described is intended to give us the same that a full year of PR and tunings plus play. Why should it be presumptuous, I don't know, may be because it is something not really understood in its physics among us humble piano repair people ? Give me a good reason why the string would be more prone to break or to tone badly if the linear plastic deformation have been lessened. Indeed plastic deformation occur also at the bridge pins, at plate pins, the strings is wrapped when the pianist play, there are cutting forces, etc. I believe it may be better to have the slack off the string, then the deformation at the bends is on a smaller zone and is not moving back and forth with pitch changes (I call that stability) Some operations described by Ed Foote, are the same as adding tension and not a little massaging the strings, leveling,) and they are to be done anyway. when the pianist play he also add tension plus other tortures to the strings Indeed the bends may well accentuate and tension may even from many points, but still the new strings goes out of tune because they are yet too plastic and under the impact and deformation made by the hammer when played they loose their tension. That is so simple I don't see why you want to argue on that. Now, on an old instrument, I certainly will not use a such heavy method unless I am certain of the strong ness of plate pins, bridge pins, bridge gluing, stiffness of the board, etc. So I will surely not use it as it is. But on modern instruments that seem to move too much, I see no reason not to try that, and it is yet done, may be not as extensively in many factories, the difference being that the pitch is raised one full tone (or more) all along the instrument, leaving the medium first plain wire not enough worked. Remember that the method say that you get a major third and the 4 plain wire, up to a minor third 17 notes above, and the next 17 notes is yet PR "only " one tone as it is done very usually in many places. Another advantage of working from above is that one helps the bridge to stand up, and give a good amount of tension behind it. The important point is that the breaking strain of the string does not change (or is slightly better). I should tend to prefer "soft" methods , as many friends, but this is not chocking at all in fact if we understand correctly what happens. Best to all. Isaac - > >Where do you see possible problems, the deformation of the > metal occur > >anyway, it may be better to have it done while the strings > are new and > >stronger, than to add new kinks and work while pitch > raising again and > >again the piano during the first years of use. > > Not necessarily, and that's one of the points. Force > stretching strings isn't necessarily, or even reasonably assumed to be > equivalent to letting them settle naturally without being unnecessarily abused. > Also, inherent in this process is the assumption that continually stretching > strings is the principal reason for the need for more tunings when a piano is new. That is, again, not necessarily the case.
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