Pianotech

  • 1.  Order / Sequence of Regulation

    Registered Piano Technician
    Posted 05-30-2018 19:37
    Hello all,

    I'm wondering if there's a reason why so many of the published regulation sequences include repetition spring strength after the rest of the action regulation? Meaning, most start with blow distance, then let off, drop, dip, etc., then rep spring strength. (Of course, this is after one aligns and levels everything.)

    My limited experience has been that setting the rep spring first makes the other items much quicker and easier to adjust. Is there a reason why it's recommended to wait?

    ------------------------------
    Benjamin Sanchez
    Professional Piano Services
    (805)315-8050
    www.professional-piano-services.com
    BenPianoPro@comcast.net
    ------------------------------


  • 2.  RE: Order / Sequence of Regulation

    Registered Piano Technician
    Posted 05-30-2018 21:38
    Benjamin 

    FWIW, I adjust the rep spring after setting blow distance and backchecks   As you said, the strength of the rep spring has an effect on other adjustments, especially drop.  And the backcheck adjustment also has an effect on the rep spring. 

    But, as we all know, action regulation is a never ending circle.  We go through the entire process, and do it all again, sometimes even a third time.  So in the end, it all gets us the same result.

    ------------------------------
    Willem "Wim" Blees, RPT
    Mililani, HI 96789
    ------------------------------



  • 3.  RE: Order / Sequence of Regulation

    Registered Piano Technician
    Posted 05-31-2018 00:59
    Regulation order can depend on how far out of regulation the action is. One must have things in the ball park before being able to refine them and achieve reasonable stability. Most of what we field techs do is best thought of as "touch-up" regulation. The regulation order I use when rebuilding is as follows.

    1-The back and front rails of the key-frame must be bedded to key-bed.

    2-Key-frame must be spaced to action cavity.

    3-The top action bedded to the key-frame.

    4-Set top action height, strike point and glue all hammers.

    5-Find Key height and level key-set.

    6-Shape hammers to reduce mass to fit the leverage of the action. (I do this by "measuring" the inertial properties of the hammer by feel) 

    7-Action parts and strings spaced. (no escapement, hammers should block on all strings, space hammers for full shift of third string on all tri-chord unisons and not clear strings on all bichord unisons)

    8-Determine proper length for shift pedal rod and make all three the same.

    9-Unison strings set in unison phase with hammer.

    10-Set escapement of jacks. (and make sure drop is below jack escapement)

    11-Establish blow/dip/aftertouch specs.

    12-Install backchecks using rest position of hammers to determine height above key. (space to hammers)

    13-Adjust repetition springs.

    14-Set resting jack and repetition lever positions.

    15- Set shift stop so action shifts clear of one string on tri's and stays on both bi's.

    16-Set balance rail studs.

    17-Install prop rail.

    18-Install back action, damper guide rails, damper upstop rail and dampers.

    19-Install sostenuto rod and adjust position.

    20- Install all pedal rods and make damper pedal pitman to proper length. Make damper pedal stop block to stop damper pedal just slightly above where the sharp keys dampers travel. Make pedal stop for sostenuto to allow sostenuto to carry dampers slightly above the position the keys and/or lift tray take them.

    21-Adjust damper upstop rail to allow dampers to move just above where the black keys take them. This should be the same as the full damper pedal lift.

    22-Lacquer treble hammers as needed.

    23-Even out touchweight if needed by judicious use of front weights or back weights in treble.

    24-Tune and touch-up regulation/voicing as needed.





    ------------------------------
    Edward McMorrow
    Edmonds WA
    425-299-3431
    ------------------------------