I once asked that question at a manufacturer's seminar. They were advocating raising the new strings and letting them fall back to pitch. The math is that there is a T value, or Tmax, the maximum tension of a string. The pitch of that string is usually about 60% of this T value. The calculations and formulas for this can be found in a PTG publication "The Calculating Technician" on page 11. The forumula is: 1.6667 Tmax = 0.557d Since this too hard to do on email, the books says "In this Formula, T max represents the maximum safe tension in pounds and d represents the (steel) wire diameter in mils raised to the power 1.667." In other words, I wouldn't raise a string more than 30% overpull of its intended pitch. However, there is still a problem with this. Even if a string is stretched to or beyond its T value, it does not always break immediately. It is a dead string, does not sound right, and is just waiting to snap when you want to make a quick exit! They can last up to 10 years or so before they snap at pitch. Carol Beigel spending too much time at the computer on a cold, rainy Sunday afternoon!
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