Pianotech

  • 1.  Over vs. under strike definition

    Registered Piano Technician
    Posted 06-17-2020 11:58

    I admit I may have, all these years, misunderstood the definition of over and under striking. My definition has been that overstriking is when the hammer strikes the string too far into the speaking length (toward the bridge) regardless of whether the hammer core is hitting the string at 90 degrees. Under strike is the opposite. With that definition it covers the issue of how to describe the over or under strike of a set of hammers that have simply been hung too far out or in on the hammer shank.

    Anyone want to chime in on this?



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    Roger Gable
    Gable Piano
    Everett WA
    425-252-5000
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  • 2.  RE: Over vs. under strike definition

    Registered Piano Technician
    Posted 06-17-2020 12:27
    Ideally the hammer strikes at 90 degrees, and this irrespective of shank orientation to the strings (e.g. upright shanks are rarely parallel to the string plane even though the hammers strike at 90 degrees). If the hammer strikes the string before it can attain a 90 degree interface (say bore too long) it is under-striking (aka under-centering). If the hammer passes the 90 degree interface (short bore of heavily filed hammers) it is over striking (aka over-centering). These terms, in my experience, never had anything to do with the ideal strike point on the speaking length. So, whatever else we might need to consider RE strike points (a different idea really) we have always needed terms to identify hammers that over or under-strike.

    Roger has an enormous amount of experience under his belt, and I can imagine his thought process at work, so I wonder how many others may have shared his definition of over and under-striking.





  • 3.  RE: Over vs. under strike definition

    Registered Piano Technician
    Posted 06-17-2020 12:44
    I thought of it as over rotating

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    Larry Messerly, RPT
    Bringing Harmony to Homes
    www.lacrossepianotuning.com
    ljmesserly@gmail.com
    928-899-7292
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