> >>What is the angle from the speaking length to the segment on the bridge >top? And what is the angle from the speaking length to the back scale? How >much bearing does this little sucker have in the treble?<< > > Hmm, using the Lowell gauge, which gives only a relative deflection > number, >the bridge angle is 6 marks off the level of the speaking length, the >backstring is 9 marks. When the legs of the gauge are 1/2" apart, each notch >represents .001" of difference. So, by my hillbilly algebra,(using >toes,too), it >seems that the back string drops .009" per half inch, which means over the 2 >1/2 " it would drop .045" in total. Please work the angle out for me, if you >would. Sure. First, it doesn't matter what the spread is on the feet. You're not measuring drop per unit of length. You're directly measuring degrees of deviation from your baseline setting, which gives you an angle. The Lowell is 1/6° (10') per graduation, so if the bridge top segment is six graduations down from the speaking segment, the front bearing is 1°. The back segment is 9 grads down from the baseline, so the overall bearing is 9*(1/6)= 1.5°, which makes the rear bearing 0.5°. >I opined: > > At > >C6 the string definitely rises from the back of the agraffe to the > >back(distal) side of the bridge, so the agraffe would pop up if the > >threads broke. > >Ron asks: > >Or rather rotate back? > > The bridge? No, the agraffe. If the threads DON"T break, it will tend to lever the bridge back. Just trying to keep the details under control. Continuity police, you know. >Ron asks: > >What's the net bearing angle between the speaking length and the >back scale segment here?<< > > umm, I already said I had my shoes off. Can you get the angle from >knowing that the backstring drops .045" in 2 1/2" of distance? (and this >duplex has >a variety of lengths, from 2 3/4" - 1 1/2". I measured the drop on the 2 >1/2" distance). That's a lot of trouble when you have a gage that directly measures angles so easily. Zero the Lowell on the speaking length, then move it to the back length and take a reading. That's the overall bearing angle, gotten without even kicking off your Nikes. I like bearing gages that measure in degrees. >That is more than possible. I am going to hope that a new scale, lower >tension, and tightened glue joints will make this a passable instrument. The >market simply will not justify a new soundboard to rectumfry a small >segment's >slight loss of sustain. (if it was a Stei... oh well, it aint'). >Regards, > >Ed Foote RPT Chicken soup for a cold - It may not help, but it couldn't hoit. I'll hope it helps too, if that'll help. Ron N
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