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Greetings,

I've been tasked to build a Baritone.

Customer wants 28.5" scale.

I've found the tension of the brand of strings he wants to use tuned b-b to be is 167lbs at 27" scale.

Is there a way to determine what an increase to 28.5" will do to the combined tension?

tia...

Design page 1-51. Tension at pitch is proportional to string length squared.

_________________
Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

The D'Addario string tension chart has a formula for tension in pounds with length in inches.

tension = (2 * frequency * length)^2 * unit weight of string / 386.4

We want to multiply the length by 28.5/27 (which I'll call C) and see what happens to the tension as a result. Since these are all multiplicative operations, and (2*F*L*C)^2 is equivalent to (2*F*L)^2 * C^2, then we can just multiply both sides of the original equation by C^2 and voila. New tension is 167 * (28.5/27)^2, or 186lbs.

Thanks folks!