Dear John, Don't let anybody fool ya! At a minimum, you WILL have to reset capstans ( or Lifter-nuts or whatever your piano is using for lost-motion) There is not a prayer that you will come close to the specs the piano has been living with for the last few years! No way, Jose' !!! It will be a huge change in lost-motion, as the hammers are gonna be moving away from the rail on the new felt. Live with it! Take advantage of the opportunity and re-set the blow distance when you install the hammer-rest felt. Then the time spent (...as it MUST BE!) on the capstans won't go (entirely) to waste. (PSO or not, it will work a little better.) Everyone would be happier, including the piano, if you regulate the damn thing! Having gotten the blow and lost-motion correct, it's not that far to let-off and checking, with a dash of key-leveling and dip. (Oh, and don't neglect the damper-lift!) Did I mention the trapwork? Wait! Wait! Can we re-finish it, too!? Oh and.........
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