I asked this question a couple of years ago and got no response. With the "old timers" in the expanded membership, maybe someone can shed some light on this: apparently the "1/40 rule" refers to the predominant practice in factories of setting the downbearing at 1/40th of the string tension. This is accomplished by setting the string-bridge deflection angle at 1.5 deg. Does anyone know the origin or anything else about this? Any references? Bob Hohf Wisconsin
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