In a message dated 25/05/02 8:06:26 AM, wayne.hohle@sympatico.ca writes: << p.s. is there really 20 tons of pressure on the soundboard or is that on the frame and the pressure at downbearing at the bridge is something different >> Wayne; No there is not 20 tons of pressure on the soundboard. The 18/20 ton figure is from the tension on the plate. With 250 (aprox) pins, each with a string tension of aprox 180 lbs, you would arrive at aprox 22.5 tons of tension on the plate. Pressure on the soundboard is directly related to downbearing and can range from 0 pounds to ?????....... for the sake of calculation let's say that downbearing on a brand X thingee was 4 lbs per string...OK then @ 250 strings that would be 1,000 lbs of pressure on the board. A board under 20 tons of pressure would self destruct immediately if not sooner and totally without regard to crowning method used.. ;-) Jim Bryant (FL)
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