>The crown under full load of the strings is barely positive, maybe 1/32" >using a thread in the middle of the board. Is that at the long rib, where boards nearly never go concave, or in the killer octave, where they nearly always do? >I pulled out my old Baldwin downbearing gauges (don't know where these >came from). Measuring in percentages of incline difference between the >speaking length and the behind-the-bridge strings I got: bass bridge , >1+%; tenor section, 1/2%; third section, 1/2%; fourth section, 1+%. A >little excessive on the bass bridge, but otherwise not bad. What's that in degrees? I once figured Baldwin's alien bearing measurement system at something like 1.75% pre degree as a conversion (I think that's right, but it might not be). If it is, that's 0.6+° in the bass and top section, and about 0.3° in the tenor and low treble - I think. As you said, heavy for the bass, but not bad otherwise unless the board in that third section is already concave. Ron N
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