>Stacy Yoak, from the Baldwin factory, was at Reno to teach a class on >re-stringing an accu-just system. During the class, he described some >changes recently introduced in production methods to control pin torque. >The first pin holes drilled in each block are test holes, in an unused >section of the block. Pins are installed in the test holes, torque measured >and evaluated. Drill RPM and feed rate are adjusted, or perhaps the drill >bit is replaced, to bring the torque within tolerance. Only then are the >"real" tuning pin holes drilled. I talked to him a bit in the rebuilding skills class (after I showed him my dumb little agraffe installation aid), and he said that drilling a block out of the piano and then screwing it to the plate will change the pin torques as the block conforms to the plate. I haven't tested this, and he was referring specifically to ultra dense blocks, but I thought it was interesting. Ron N
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