Lowell Component Downbearing Gauge

[Erwinspiano at aol.com]

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