At 23:45 -0600 11/2/09, Michael Magness wrote: >My understanding (2nd hand)Êis that he only does the analysis of the >break based on the composition of the metal which is usually >provided to him. He is involved in Homeland security contract work >and offered to do this for his father whose piano I rebuilt and had >the problem string(s) on. Wound strings which broke at the loop, >something I have only had happen once in my 40 years in the business >prior to these. If you mean they break at the point where the eye meets the spiral twist, then there are two possible causes. The first is that the eye has too many twists in relation to its length, which creates stress at this point, and the second is excessive tension, which I suppose you have already eliminated as he cause by calculating the tension of the string. If the core wire is too hard (or brittle) then it is difficult or impossible for the stringmaker to make the eye to start with without its breaking on the eye-making machine. There is one make of German wire that I cannot use for bass strings for this reason -- that above size 23 the wire snaps when you try to make the eye, but usually along the twist rather than at the point above. All such breakages will occur very early in the life of the string. JD
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