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Sluggish Upright Jacks

  • 1.  Sluggish Upright Jacks

    Registered Piano Technician
    Posted 12 days ago
      |   view attached
    Dear Colleagues,

    I'll be going to see a 1925 Craig upright, made in Montreal. Quite a well-made piano judging by the photos I've been sent, and in quite good condition (although I haven't seen it yet) but it looks to have a widespread problem with sluggish jacks not resetting after a few blows. The owner has sent me a pretty nice video, which I've attached. I should mention that the piano lives on an island in the Salish Sea, so there's that.

    What system-wide remedy do you think might be most effective? CPL? CBL? Vodka (50/50)? Pure alcohol? Plus heat? I will repin the worst if treating the jack center pins is not fully effective, but repinning every jack is not something on the table right now. And since I have to take a ferry to see the piano I want to be as prepared as possible.

    Your collective experience will be most appreciated.

    David Trasoff

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    David Trasoff
    Whatcom Piano Service
    (360) 389-2158
    david@whatcompianoservice.com
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  • 2.  RE: Sluggish Upright Jacks

    Registered Piano Technician
    Posted 12 days ago
    I ran into a similar issue with an old Wurlitzer 200 Electronic Piano this summer.  Hammer, wippen and jack flanges were all sluggish.  I did an initial treatment with CLP, but the results were not satisfactory.  I ended up repinning the works, and the customer was delighted with the results.


    I've come to the point where I might use CLP for the odd slow flange, but if I have a systematic problem, repinning is the solution, if there's going to be a lasting solution.

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    Floyd Gadd
    Regina SK
    306-502-9103
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  • 3.  RE: Sluggish Upright Jacks

    Registered Piano Technician
    Posted 12 days ago
    You might also check that the rest rail hasn't settled to the extent of no lost motion. It may be just compacted felt where the rest rail sits on the action frame. Uprights need a little lost motion.
    May also involve key height, or blow adjustments.
    This occurred to me because the jack sounded and looked like it moved freely- just blocked against the butt.
    Nancy Salmon, RPT





  • 4.  RE: Sluggish Upright Jacks

    Registered Piano Technician
    Posted 12 days ago
    Hi David,

    For most cases (not plastic flanges or verdigris infected actions), I use Ballistol (with a syringe) and work the solution into the center pin with a hairdryer (not too hot), and rapidly move the flange with my hand to work in the lubricant.

    I would test this by removing the one flange and see how well it works. If it works then you should probably apply the solution to all the jack flange center pins (outside the piano so as to not heat up the strings) and rapidly move the JACKS (correction) with your hand. There is never just one sticking note.

    In the video, I notice that the player is not properly repeating the note. The note is being played as if it is on a grand piano. The fingers should be lifted higher to allow the jack to fully return in this upright. HOWEVER, I see that the jack is lifting more vertically, indicating that the flange is indeed sluggish.

    Paul.


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    Paul Brown, RPT
    Past President
    Piano Technicians Guild
    Vancouver, BC Canada
    Email: ipp@ptg.org
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  • 5.  RE: Sluggish Upright Jacks

    Posted 10 days ago
    Hello Paul,
    have you ever gotten any complaint about the smell of the Ballistol?
    Peter

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    Petrus Janssen
    Peachtree City GA
    678-416-8055
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  • 6.  RE: Sluggish Upright Jacks

    Member
    Posted 10 days ago
    CBL works great in this application. If I do say so myself :-)

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    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
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  • 7.  RE: Sluggish Upright Jacks

    Registered Piano Technician
    Posted 10 days ago
    Hi Petrus,

    I warn them before using it. I've only had one complaint that I can think of.

    Paul.

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    Paul Brown, RPT
    Past President
    Piano Technicians Guild
    Vancouver, BC Canada
    Email: ipp@ptg.org
    ------------------------------



  • 8.  RE: Sluggish Upright Jacks

    Posted 8 days ago

    Seeing that the piano is in an out of the way location, on an island involving time and expenses to get there, you cannot afford a call-back.
    Lubricants can get you out the door but are often not a permanent fix.

    Truly, the only fix that is guaranteed on sluggish jacks is re-pinning.
    As others have mentioned, other factors could be involved - lost motion, sluggish keys, weak jack springs etc



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    Jurgen Goering
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  • 9.  RE: Sluggish Upright Jacks

    Member
    Posted 8 days ago
    I think you need to look at the overall regulation situation and make sure there is some lost motion in the key so the jack can clear the hammer butt. New rest rail cloth could solve lots of problems however then you will need to re-regulate for blow, letoff, backchecking, lost motion, etc. One way to test for weak springs is to tug a little on the springs to stretch them and see what difference it makes. Make sure the keys are not too tight on the key pins and ease as needed. I recently worked on a Kimball consolette made in the late 1950's that had several keys with the same issue. Adjusting lost motion, letoff, easing the balance key pin hole, cleaning and polishing the keypins and adjusting backchecks solved the issues. I did not do any lubrication , stretching springs or repinning. I used a jig that was about 10" long and 5/8" thick , wedged the hammer rest rail so the hammers where 1/8" from the strings- the result was a fast and consistent letoff of 1/8" when it had been all over the map.

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    James Kelly
    Owner- Fur Elise Piano Service
    Pawleys Island SC
    843-325-4357
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  • 10.  RE: Sluggish Upright Jacks

    Registered Piano Technician
    Posted 5 days ago
    Here's a follow-up to the upright piano with sluggish jacks. First, a tip of the hat to Geoff Sykes, who sent me a private note suggesting that I lift the key with the sluggish jack - if the jack reseats it's probably a key bushing issue; if it doesn't it's the jack. The likely answer was evident as soon as I got to the piano and disassembled it. As you can see in the attached photo, what couldn't be seen before was that the keyboard had been rebushed. Not a horrible job, but not carefully enough for the circumstances. The 'sluggish jacks' were all the result of keys dragging on the front rail bushings, the jacks worked fine (I lubricated them with CBL anyway). I eased and treated things as much as possible, but the damp climate is likely to continue to be an issue. Even more concerning, I found as I got more into it that many of the front key pins were corroded, so there may be more work ahead.

    Thanks to everyone for their suggestions.


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    David Trasoff
    Whatcom Piano Service
    (360) 389-2158
    david@whatcompianoservice.com
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