Pianotech

  • 1.  Huntington Grand Regulation - trying to get close letoff

    Member
    Posted 06-09-2017 00:24

     I replaced all of the hammers, shanks and flanges on a Huntington grand piano and am trying to set samples to begin action regulation

    Samples where sent out for duplication so there is no question about the bore, knuckles etc . I adjusted the capstans to get get the shanks off the rebound rail felt, added some strength to the rep springs, cleaned and polished keypins, adjusted backcheck , adjusted letoff and drop etc but my problem is I can not get letoff anywhere close to the string at present it is like 1/2 inch away. I did not check the glide bolts but I did notice that the piano has about a half dozen glide bolt studs coming up through the front of the keybed that could/should/would lift the keyframe at the front rail and change things. I noticed a feature called the patented touch regulator that was used in Mehlin pianos to regulate touch depth. Does anyone know what these studs do and how to adjust them
    .
    Howe can I get closer letoff in this action . I did not change out any bushings or punchings and perhaps I have to experiment more to get the proper key heights and depths. I have not found any starting point regulation specs. Unfortunately the piano was in a high humidity
    situation after flooding and all of the hammer felts peeled off the moldings. Maybe I need to look into replacing the keyend felt ????
    I have no idea what condition the piano was in before I got to. The action looked like it had been hardly touched and only had moderate wear.  I am aware of some articles published in 2000 (may June,Aug Sept) on action elevations and will try finding them on my Journal CD collection



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    James Kelly
    Pawleys Island SC
    843-325-4357
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  • 2.  RE: Huntington Grand Regulation - trying to get close letoff

    Registered Piano Technician
    Posted 06-09-2017 02:03
    James

    OK, you need to figure out why the lo is at 1/2". Look at blow distance. Look at jack position on the knuckle, make sure the drop screw is not interfering with lo.  The front rail could be higher.

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    Willem "Wim" Blees, RPT
    Mililani, HI 96789
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  • 3.  RE: Huntington Grand Regulation - trying to get close letoff

    Registered Piano Technician
    Posted 06-09-2017 02:14
    James -
    Your first problem is that you're up at this at 12:24 AM.
    Second, that you think that there could be no question about bore because you sent them out or duplication.  How would they have done that i all the hammers lost or had otherwise deformed felt?
    Meanwhile, you didn't bother to send some basic numbers:  string height, hammer flange centerpin height, hammer bore in bass and treble, hammer blow, key dip...?  

    What else was done with this flood victim?  Or, or that matter, what else happened to it?  Was it rebuilt?  Is it thoroughly dried out?
    As a rough starting point for establishing key height, they have to fit under the fall board and below the key slip. The naturals have to have sufficient clearance with the top of the keyslip with a 10mm key dip. They have to have adequate balance rail  pin protruding from above the keys and have sufficient front rail pin projecting into front mortise.  Ideally, you'd have room under balance cloth for some amount of paper punchings and likewise at the front rail.  

    The glides at the front should start out turned down and be used to bed the front rail, I believe.








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    David Skolnik
    Hastings-on-Hudson NY
    914-231-7565
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  • 4.  RE: Huntington Grand Regulation - trying to get close letoff

    Member
    Posted 06-09-2017 08:26
    I should have been more clear about the existing hammers. I sent many samples that still had felt on them but in some cases a few hammers had felts that came completely off however the felt and hammers where numbered . I do not think there are issues with any of the lengths, bore etc but that I am, going to have to go over a number of samples in each section to get this action to work. I think this is one of those pianos that may have never been properly regulated after some type of rebuilding and somebody just got it to work good enough to sell it . Thanks for some ideas. Yes my post was late but it gives it a chance to get answered during the night. I am on the east coast but plenty of techs are up with all of the time zones w have plus our clocks are all different in our heads.
    Wim... what time is it there when it is 1230 am here ?

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    James Kelly
    Pawleys Island SC
    843-325-4357
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  • 5.  RE: Huntington Grand Regulation - trying to get close letoff

    Registered Piano Technician
    Posted 06-09-2017 13:30
    Wim... what time is it there when it is 1230 am here ?

    You're 6 hours behind me. 12:30 AM is 6:30 PM here. 

    It's neat to have members all over the world. From here, Israel and I are 12 hours apart. One of our sons lives in Malaysia. He's 6 hours ahead of us, but the next day. 


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    Willem "Wim" Blees, RPT
    Mililani, HI 96789
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  • 6.  RE: Huntington Grand Regulation - trying to get close letoff

    Registered Piano Technician
    Posted 06-09-2017 11:01
    James,
    You mention that you replaced the hammer shanks. Are the knuckles on the new shanks the same diameter as the old knuckles?
    Roger

    Virus-free. www.avast.com





  • 7.  RE: Huntington Grand Regulation - trying to get close letoff

    Registered Piano Technician
    Posted 06-10-2017 10:30
    James,
    I'll just speak to the front rail glides, having recently bedded a Chickering that has them. My method was to turn them all down (from underneath the piano), install the action, and raise each glide to .20", using a feeler gauge, then check for knocking.
    Scott

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    Scott Cole
    Talent OR
    541-601-9033
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  • 8.  RE: Huntington Grand Regulation - trying to get close letoff

    Member
    Posted 06-10-2017 13:00
     I believe this piano was "rebuilt" but not regulated very well judging from what I am finding. Key dip is 7mm only one worn down felt punching on the balance rail, thick cardboard punchings under front felts, shanks on the rail felt and little to no tension in the rep springs. I am sorting it all out on several samples in each section including starting with the big three and getting key height , back checking , letoff and drop on the samples . As LaRoy would say get it right once and duplicate it 87 more times...

    BTW in response to knuckle size- the hammers were sent out to be duplicated. There are 6 glider bolts in the keybed and 4 on the frame. Bedding seems fine but will recheck it


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    James Kelly
    Pawleys Island SC
    843-325-4357
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  • 9.  RE: Huntington Grand Regulation - trying to get close letoff

    Registered Piano Technician
    Posted 06-13-2017 15:50
    James,
    7 mm dip is not going to get you through a full action cycle in any piano built since the mid 1800s. You would almost certainly need 9.5 mm at a minimum.I'm not sure what you mean by not being able to get let off closer than 1/2", but if it is a matter of getting the action through let off, increasing dip is definitely the first step. (It could also mean not being able to screw the let off buttons up high enough).

    So create enough key height that you can get about 10.5 mm dip (for a safety factor), then try out various blow distance/dip combinations until you get one that works. Creating key height is a combination of balance punchings and back rail cloth, so experiment with that as well: combination of a back rail cloth thickness and a balance punching that gets you close to your target - with a thickness of front rail punching thrown in.

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    Fred Sturm
    University of New Mexico
    fssturm@unm.edu
    http://fredsturm.net
    http://www.artoftuning.com
    "We either make ourselves happy or miserable. The amount of work is the same." - Carlos Casteneda
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  • 10.  RE: Huntington Grand Regulation - trying to get close letoff

    Member
    Posted 06-13-2017 18:00
    What it all comes down to are two things- getting the key height up and removing the thick felt letoff felt someone put on the letoff buttons. Of course I had to bring the hammers up to a blow distance that would work . Now that I have gotten some samples to work its time to replicate things. The balance rail pin bushing was only 1 worn down felt and most of the front pins had felt and cardboard. On my samples I managed to get good letoff and drop only after cutting off the thick punching on the lo buttons. I have some smaller felts that should work fine. As far as dip I was able to get 10mm . Sometimes we need a can of worms so we can have some fun

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    James Kelly
    Pawleys Island SC
    843-325-4357
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