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Regulation Question

  • 1.  Regulation Question

    Posted 3 days ago
    I am engaged in doing a "minimal" regulation to an old Wurlitzer grand piano that better deserves a burial in the county dump. However, it is one of these many pianos that while being rather worn out, unfortunately, nothing has completely broken yet - so it lives (limps?) on. Besides, it's a family heirloom (betcha couldn't have guessed that!).

    The hammers were bobbling upon being played - insufficient key dip - notes didn't go through letoff - hence the minimal regulation to restore function (I love that term as it relates to regulation).

    I leveled the keys, setting key height so that it works with the keyslip and fallboard and so that there would be adequate key dip with the felt front rail punching in place (Randy Potter's Piano Handbook worked here!!!). Sharps are 1/2" taller than naturals. With blow set to 1-7/8", I regulated letoff for both naturals and sharps. The naturals have pretty close to 10mm dip with minimal aftertouch - works for me. However, with enough dip to complete letoff plus a tiny amount for aftertouch, the sharps end up well below the naturals. It's like there is drastically differing action ratios between naturals and sharps.

    Clearly a new, properly designed, keyset would remedy the situation. However I told the piano owner that I'd try to do a functional regulation for a shamefully low price.

    Anyone care to suggest a simple fix?

    I know I could just raise the height of the sharps, but the sharp keysticks are already taller than the natural keysticks - I'm concerned that any higher would risk interference with the fallboard. Plus, the sharps at rest are already almost exposing the bottom of the ebony sharp (would look real tacky). I could lessen blow and drop natural key height - hate to do that as playing the piano would make it feel like a harpsichord with the resultant shallow keydip. Unfortunately, as we all know, doing one thing affects many other things when regulating.......

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    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
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  • 2.  RE: Regulation Question

    Member
    Posted 3 days ago
    I'd bag the 1-7/8 blow to start. 1-5/8 can be used without most folks realizing it, even on well regulated actions. I don't do that unless I need to, but the reduction in blow is really not that much of a biggy. If you're still having letoff/aftertouch problems on the sharps, widen up letoff a little too. Have you checked the jack positions?  In an old action, they may have settled way back into the jack rest felt, thus making the jack travel ridiculously far to letoff, not to mention feeling really weird being on the wrong side of the knuckle. Not being regulated in the last millenium, this has a reasonable chance of being an issue.

    "edit my original post said "dip", where it should have said "blow"...oops...mind fart

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 3.  RE: Regulation Question

    Member
    Posted 3 days ago
    I should have said, the reduction in blow if dip is not too adversely effected, is not a biggy.  If your hammer line looks wildly jagged, because sharps require it but not the naturals, I would not hesitate to do that for a moment, in this situation...as the goal is minimum functionality, rather than impressive anal regularity.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 4.  RE: Regulation Question

    Registered Piano Technician
    Posted 3 days ago
    What Jim said. The hammers could easily be .25" shorter than they originally were. Probably more.

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    Steven Rosenthal
    Honolulu HI
    808-521-7129
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  • 5.  RE: Regulation Question

    Member
    Posted 2 days ago
    If worse comes to worse, you can relocate the sharp's capstans further back on the keys. It sound like the distance between the natural and sharp balance rail pins is too great (sharps being too far back). IOW, irregular Key Ratio.

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    Regards,

    Jon Page
    mailto:jonpage@pianocapecod.com
    http://www.pianocapecod.com
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  • 6.  RE: Regulation Question

    Registered Piano Technician
    Posted 2 days ago
    Terrance, following up on Jon Page's suggestion of an irregular key ratio:  You might try trimming the balance-rail punchings to move the effective keystick fulcrums.   Move the natural fulcrums aft, and the sharp fulcrums forward.

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    John Rhodes
    Vancouver WA
    360-721-0728
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