Pianotech

  • 1.  Yamaha G3 Action Geometry

    Posted 04-28-2021 11:42
    I am just getting under way in working over the action in a 1965 Yamaha G3.  I started out assuming I was dealing with the original hammers and shanks, and that may well be the case, but I'm now a little less sure, as Balance Weight is coming in at upwards of 50 grams, at least in the overstrung section, which is what I have measured thus far.

    I have a few puzzles facing me here around action ratio and, for that matter, action height, but I need to take some more measurements before I can ask intelligent questions.

    One question I think I can ask right now pertains to the fact that the difference between the hammer action center height and the string height in  the plain wire section sits at about 53mm,  and the two sets of "new" factory hammers that have been sitting around here for a few decades have a bore distance of 50mm.  I am inclined to shim up the action stack by 3mm, provided that stretcher height, magic-line considerations, and capacity for capstan adjustment don't suggest that this is a bad idea.  I still have to make those assessments.  Does this strategy otherwise make sense?

    ------------------------------
    Floyd Gadd
    Regina SK
    ------------------------------


  • 2.  RE: Yamaha G3 Action Geometry

    Registered Piano Technician
    Posted 04-28-2021 19:23
    Floyd,
    The stock hammer and shank assembly you have may be the correct bore distance for the G3 you have. Keep in mind that the hammer shank should be parallel to the string when struck -- not the keybed. Check to see if the hammer shank is parallel to the string by using parallel measuring device.
    Roger

    ------------------------------
    Roger Gable
    Gable Piano
    Everett WA
    425-252-5000
    ------------------------------