William Truitt wrote: > Hi Ron: > > Is there a target breaking percentage you try to aim for when doing this > sort of rescaling? Not really. I try to get A-0 into the high 30s, low 40s. >How far up from the bottom are you decreasing the core > sizes and increasing the wrap? Not necessarily increasing the wrap. I'm watching tension, Z, break%, and how the transitions blend. It's not a standard deviation from the original, because the original could be literally anything. >Is there a core size to wrap size ratio that > you do not want to exceed? Not as such (I don't have a number "rule"), but there are considerations. In a large piano, I'll likely do a 0.051" core at A-0 if I can make it fit. In a smaller piano that has a heavy wrap because of the string length, I'll go with 0.053" core. While the smaller piano could benefit from a more flexible bass string, it's harder for the string maker to wrap on the smaller core. The whole thing is a series of balanced compromises. >Finally, since the tensions increase as well, > what limits do you want to respect? > > Will Bass tensions in my scales, overall, tend to decrease slightly. When they do increase, I try to keep it within a couple of hundred pounds total. I try to limit break% in wrapped strings to 55% with Sanderson's formula. I go over sometimes, but not by much. Ron N
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