Thanks, Joe You're right about the typical breaking %, but my point was just that the bends we put in the wire are weak spots and are closer to the breaking point. So that even though the Mason & Hamlin 9 foot string AO calculation you mentioned puts it at 75%, the bends in that string must be closer to 100%. Gordon Large, RPT Maine -----Original Message----- From: Joseph Garrett <joegarrett at earthlink.net> To: pianotech <pianotech at ptg.org> Sent: Tue, Mar 2, 2010 5:01 pm Subject: Re: [pianotech] String breakage Gordon said: "When a string is at pitch, it's usually around 60% of the tension that would cause it to break." Gordon, That is a false statement for the most part. Most strings are in the 35% to 55% of breaking strength @ pitch. There are exceptions, but are generally few and far between. Most Yamaha scales are "High Tension Scales", so you will find that string breakage is more common, especially with the U.S. made versions. The example of a 1900 So/so Grand and how far one had to twist the t.pin to get the string(s) to break, was an example of a Medium or Low Tension Scale. Just FYI, the thicker the soundboard and the stiffer the soundboard assembly is, the higher tension and the harder the hammer is required to get decent (?) sound production. The best example of a string that WILL break, is the M & H 9footer - A0. That string is at around 75% of breaking strength, at pitch and WILL break. (Soooner than later! <G>) Regards, Joe Joe Garrett, R.P.T. (Oregon) Captain, Tool Police Squares R I -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech.php/attachments/20100302/667b6f19/attachment.htm>
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