more heresy

[Ron Nossaman]

At 02:02 AM 9/16/97 -0500, you wrote:
>
>
>----------
>> From: Hrschm@aol.com
>> To: pianotech@ptg.org
>> Subject: Re: more heresy
>> Date: Monday, September 15, 1997 7:46 AM
>> 
>> In a message dated 97-08-20 10:46:44 EDT, you write:
>> 
>> << 
>>  Estimates of string downforce against the bridges of modern pianos
>>  varies from about 0.5% to 1.5% of overall scale tension. 
>
>
>
>
>Is there a formula to compute this down bearing?  I am looking for
>one that computes the down bearing of a single string, given its
>tension and deflection.
>Richard Moody 
>
>



I posted this in July, didn't you guys get one of these?



   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