Hi all,
Here's the new bearing chart I promised (if anyone's interested),
incorporating the gauge calibration of the Baldwin and Lowell bearing gauges.
Bubble reading to Degrees to Bearing Load conversion
for Lowell and Baldwin downbearing gauges.
Measure bubble offset difference between string segments
on both sides of the bridge. Look up angle and bearing factor
on appropriate chart. For bearing load in pounds, multiply
bearing factor times string tension.
Ron Nossaman July 27, 1997
Baldwin Gauge | Lowell Gauge
------------------------------|-----------------------------
Bubble Angle Bearing | Bubble Angle Bearing
------------------------------|-----------------------------
0.5 0.14167 0.0025 | 0.5 0.09375 0.00164
1.0 0.28333 0.005 | 1.0 0.1875 0.00327
1.5 0.425 0.0075 | 1.5 0.28125 0.00491
2.0 0.56666 0.01 | 2.0 0.375 0.00655
2.5 0.70833 0.0125 | 2.5 0.46875 0.00818
3.0 0.84999 0.015 | 3.0 0.5625 0.00982
3.5 0.99166 0.0175 | 3.5 0.65625 0.01145
4.0 1.13332 0.02 | 4.0 0.75 0.01309
4.5 1.27499 0.0225 | 4.5 0.84375 0.01473
5.0 1.41665 0.025 | 5.0 0.9375 0.01636
5.5 1.55832 0.0275 | 5.5 1.03125 0.018
6.0 1.69998 0.03 | 6.0 1.125 0.01963
6.5 1.84165 0.0325 | 6.5 1.21875 0.02127
7.0 1.98331 0.035 | 7.0 1.3125 0.02291
7.5 2.12498 0.0375 | 7.5 1.40625 0.02454
8.0 2.26664 0.04 | 8.0 1.5 0.02618
8.5 2.40831 0.0425 | 8.5 1.59375 0.02782
9.0 2.54997 0.045 | 9.0 1.6875 0.02945
9.5 2.69164 0.0475 | 9.5 1.78125 0.03109
10.0 2.8333 0.05 | 10.0 1.875 0.03272
10.5 2.97497 0.0525 | 10.5 1.96875 0.03436
11.0 3.11663 0.055 | 11.0 2.0625 0.036
11.5 3.2583 0.0575 | 11.5 2.15625 0.03763
12.0 3.39996 0.06 | 12.0 2.25 0.03927
12.5 3.54163 0.0625 | 12.5 2.34375 0.0409
13.0 3.68329 0.065 | 13.0 2.4375 0.04254
13.5 3.82496 0.0675 | 13.5 2.53125 0.04418
14.0 3.96662 0.07 | 14.0 2.625 0.04581
14.5 4.10829 0.0725 | 14.5 2.71875 0.04745
15.0 4.24995 0.075 | 15.0 2.8125 0.04908
15.5 4.39162 0.0775 | 15.5 2.90625 0.05072
16.0 4.53328 0.08 | 16.0 3. 0.05235
Ron Nossaman
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