Yes Paul I believe this is right. I've always used Nick Gravagnes formula. The length of the backscale starting at the front bridge pin Times .026 = 1 1/2 degrees. i.e. a 4 inch rear length times .026 ==.104 thousands of distance bearing. The Only problem with all this extrapolation as I see it is that the rear foot of the lowell gauge sits behind the rear bridge pin, which is usually sitting lower than the actual elevation of the aliquout (or Whatever Del,Terry..grin). WHich means the gauge may actually read more bearing present than there is. Why? Hmmmm... Because of bridge slope to the rear & the grasp of the bridge pins. Of course the opposite could be true. Dale Terry: The conversion from the mils measurement (thousandths of an inch) to a tangent value is straightforward. If I recall correctly, 3 units to the positive bearing from both sides of the bridge (net) yields 6 x 0.003"=0.018 which is the tangent of 1 degree net bearing over the bridge. Hmmm, maybe I have to look up my tangent tables to be sure of this, but I think it's right. 0.026 is the tangent of 1 1/2 degrees, I think. Anyway, that's the conversion. And someone should make that clear with the instructions, you're right. Paul ************************************** See what's free at http://www.aol.com. -------------- next part -------------- An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20070504/652ae086/attachment.html
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