Pianotech

Expand all | Collapse all

Hamilton Grand Regulation

  • 1.  Hamilton Grand Regulation

    Member
    Posted 01-01-2018 15:37
    Happy New Year !!!!

       I am trying to finish the regulation on a Hamilton grand but for some reason I can not get letoff close to the strings on many notes. 

       The original whippens are in the piano and are in good condition although it is difficult to adjust the rep springs which have a screw that can touch the knuckles if it too far from the balancier. 

       I had new hammers, shanks and flanges made from samples I sent and they sound great but the regulation is all over the place. I had to add punchings at the balance rail and front key pins since there was only 1 felt punching on each keypin. I also replaced all of the backchecks and
     the hammer rebound rail .

     The action screws down on the keybed with small blocks on the pins that are on the keyframe.

     Perhaps I should replace the backrail cloth ?  

    There are 6 glider bolts located under the front action frame rail  that are adjustable from under the keybed 
    These were screwed down all the way when I started however I brought them up using a feeler gauge and using the
    measurement someone gave me in a prior thread I started on this piano.
    The piano really was a mess when I started working on it and barely worked with no power or even response and had
    no aftertouch.

    The capstan screws are the Moore style that has slots in them making them hard to align with capstan tools . I have cranked them up from when I first started . I also re-pined some of the whippens to better support the weight of the new hammers and assist with repetition

    Perhaps I need to look into shimming the action rail but maybe the rep lever springs are the culprit. I read an article about rep springs that had been bent improperly so that the tension needed to perform properly was lost. I also read a great article from the late Susan Graham about problems that come from action renovation due to felt issues.   
    I have used the case parts to get key height so the front bottoms of the key front do not come above the top of the key slip and there are no problems with the fall board.

    What can I do to get the letoff to happen closer to the strings  ?  I am thinking of trying a swap out of a whippen and using one with a butterfly rep spring to test if it is the whippens. 





    ------------------------------
    James Kelly
    Pawleys Island SC
    843-325-4357
    ------------------------------


  • 2.  RE: Hamilton Grand Regulation

    Posted 01-01-2018 16:48
    Dimensions you should check:
    Action spread                  AS
    Hammer Center Height.  HCH
    Wippen Center Height.   WCH
    String Height                   SH
    Hammer Bore Length.     HBL


    In an ideal world:
    SH - HBL = HCH (also dependent on pitch of bore) striking string at 90 degrees (under striking slightly for new hammer to wear in)
    HCH - WCH = 6.4 mm
    AS has the knuckle core pointing at the jack center at rest.



    ------------------------------
    Regards,

    Jon Page
    ------------------------------



  • 3.  RE: Hamilton Grand Regulation

    Registered Piano Technician
    Posted 01-01-2018 17:35
    Since this piano has been around for a while, and you are replacing h/sh/fl and doing a complete regulation, I would highly recommend replacing all of the keyframe felt. It doesn't take that much time and the materials are not costly. Doing so would be in keeping with the thorough job you have set out to accomplish. And while you're at it, the key pins probably need either cleaning/polishing and lubricating, if not replacement. 

    Alan

    ------------------------------
    Alan Eder, RPT
    Herb Alpert School of Music
    California Institute of the Arts
    Valencia, CA
    661.904.6483
    ------------------------------



  • 4.  RE: Hamilton Grand Regulation

    Registered Piano Technician
    Posted 01-01-2018 18:15
    …make that "keyframe cloth and felt" (back rail cloth, and possibly crescendo felt key pin punchings).

    Alan

    ------------------------------
    Alan Eder, RPT
    Herb Alpert School of Music
    California Institute of the Arts
    Valencia, CA
    661.904.6483
    ------------------------------



  • 5.  RE: Hamilton Grand Regulation

    Registered Piano Technician
    Posted 01-01-2018 18:42
    Jim,

    You say " I can not get letoff close to the strings on many notes. "??
    So,?? you are getting letoff but it's not high enough. So, all this talk
    about keyframe felt, capstain height, rep springs, etc. is missing the
    point.?? If letoff is too low, it means the jack is not pushing the
    knuckle high enough before the tender meets the letoff punching.?? Those
    are the three components you need to focus your analysis on:?? Knuckle,
    jack, and letoff button.?? I trust you've adjusted the letoff buttons as
    high as they will go.?? Still not high enough??? Replace the letoff
    punchings with thinner cloth.?? Still not high enough??? Thinner letoff
    buttons, modify / raise the letoff rail, etc.

    Mike




  • 6.  RE: Hamilton Grand Regulation

    Posted 01-01-2018 18:54
    Perhaps the shanks were replaced with a longer knuckle radius, ie: 15.5 mm to 17 mm. If the LO is too low, look at shimming the top action to raise the HCH.

    I had one Steinway where I had to modify the rep lever end felt and jack tender. Thinner felt and cut the rep lever, sanded the jack to lower the height of the nub. These modifications allowed the Jack to trip out later and the unstop screw to be lowered from it's 'bottomed-out' position.


    ------------------------------
    Regards,

    Jon Page
    ------------------------------



  • 7.  RE: Hamilton Grand Regulation

    Registered Piano Technician
    Posted 01-02-2018 09:36
    Hi Jim,  I agree with Micheal's assessment and suggestions.  Focus on the jack, tender, let off button relationship before changing things.

    The question remains, what was changed in the piano's past that caused this in the first place. 

    You've mentioned replacing the hammer rest felt  .....  I think.  You've achieved the proper relationship between the keys and the cabinet.  The relationship between the strike point of the hammer and the strings has to be established as well.  Strike distance.  Too much window and let off will occur way too soon. 

    H/S/Fl's were replaced.  Assuming the correct knuckle was in the piano in the first place, and assuming the vendor properly selected/replaced the parts for you, all you should have to do is reset the blow/strike distance and you should be close with all the other settings.

    So many items have been replaced and that adds to the possibilities of problems.  Eliminate them all as sources of your problem before replacing anything else.

    The action was a mess before you started.  Aiming a bigger shot gun at it isn't going to help.  Move forward methodically and carefully making dang sure you haven't added more problems as you go.  Focus on one note and it's function.  Get it to work perfectly first taking note of what you do and apply your findings to the rest of the action  .......  one note in each section to start, then fill in later.

    Action regulation can sure tie a person's hands in knots if it's not done right.  We're not action design engineers and so we typically don't need to apply our skills at such a critical level.  Action spread, starting position, cabinet parameters, and relationships were supposed to all have been established when the piano left the factory.  It sounds like someone at some time messed that up.  Put on your Sherlock Holmes cap and locate the problem.  Good luck.

    ------------------------------
    Larry Fisher
    Owner, Chief Grunt, Head Hosehead
    Vancouver WA
    360-256-2999
    ------------------------------



  • 8.  RE: Hamilton Grand Regulation

    Registered Piano Technician
    Posted 01-01-2018 20:49
    James

    As was mentioned, you have t o figure out why the jack is not escaping from the knuckle. There is nothing wrong with increasing keydip ever so slightly by just .05, to get the jack to escape. Go from that aspect and you will find the answer. 

    The other problem you alluded to was the rep spring. There needs to be a nice bend in the spring in order for it to work. Remove the wips and  re-bend each one if you have to.

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



  • 9.  RE: Hamilton Grand Regulation

    Registered Piano Technician
    Posted 01-02-2018 08:02
    Hi James

    Happy New Year.

    Is it that the letoff buttons are bottoming out before letoff is at the correct height? Or is it that as you turn the letoff buttons up, letoff becomes no longer visible, and the hammer doesn’t drop?
    If the second scenario is the problem, it’s because the dropscrew needs to be adjusted.
    If the first scenario is the problem, take Fred’s advice and change the thickness of the letoff felt. Also, make sure you tighten any screws that hold the letoff rail on.

    This is why before going through an entire regulation, a best practice is to set a sharp and natural sample in each section, and regulate them out to see if you will run into any problems.

    Good luck!
    Elizabeth




  • 10.  RE: Hamilton Grand Regulation

    Registered Piano Technician
    Posted 01-02-2018 10:21
    James,

    It is looking to me like small changes in dimensions in the new parts are  compounding a problem that probably already existed in the piano. (Close comparison of old and new parts...)

    Therefore you may have no choice but to treat the symptom rather than the problem at this point. If the primary issue is let-off I agree with changing cloth thickness on the buttons (even though the cause of the problem is probably related to the knuckle, hammer bore, or both). Or you may even need to change the buttons themselves if you can get a thinner one.

    The rep springs are probably an issue now because the hammers are heavier, and the springs are weaker than they used to be. Be careful about moving the whippen rail. That can have unintended and unforeseen consequences (don't ask me how I know that).  Look for possible warpage or curve somewhere. It has happened to me on older actions.

    Sometimes you have to just do the best you can with what you are given.  Sounds philosophical I know...

    Pwg

    ------------------------------
    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
    ------------------------------



  • 11.  RE: Hamilton Grand Regulation

    Posted 01-02-2018 10:09
    James-
    Your first sentence states " I can not get letoff close to the strings on many notes."
    Does this mean that you also can get letoff close to the strings on some notes?
    If so, then compare carefully the ones that work with the ones that don't work, and this may give the answer to your problem.


    ------------------------------
    Ed Sutton
    ed440@me.com
    (980) 254-7413
    ------------------------------



  • 12.  RE: Hamilton Grand Regulation

    Posted 01-02-2018 10:21
    I had this problem on a Mason & Hamlin CC with newish hammers and shanks.  It turned out some of the hammers had been mis-drilled.  I suppose I should have plugged and re-drilled, but I ended up bolstering the knuckles with yarn to achieve the let-off I needed.  Users seem happy with the instrument.

    ------------------------------
    Floyd Gadd
    Regina SK
    306-502-9103
    ------------------------------



  • 13.  RE: Hamilton Grand Regulation

    Registered Piano Technician
    Posted 01-02-2018 10:30
    "The action screws down on the keybed with small blocks on the pins that are on the keyframe."

    Unfortunately I can't add anything to the answers given. But It does bring up a slightly different topic....

    About a year ago I tuned a Hamilton Grand. A few days later I got an email from the owner that he had decided to unscrew the action, and that as a result he felt it played and sounded better. I said the action was meant to be screwed down, but he said no, maybe it was just for transport.

    Ok, whatever. If he likes his work, he likes it. He's the customer.

    My question on this subject is whether, if there is now a slightly different position as a result of being unscrewed, could there be stress put on the hammer flange centers if the hammers are grooved? Could there be any other deleterious effects other than possible knocking noises?

    ------------------------------
    Scott Cole
    Talent OR
    541-601-9033
    ------------------------------



  • 14.  RE: Hamilton Grand Regulation

    Registered Piano Technician
    Posted 01-02-2018 11:02
    Scott,

    If the pressure from the blocks is significant it can cause the front rail (or maybe even the balance rail) to bow up on the middle. This would certainly create performance issues. I have seen this happen. 

    Pwg


    ------------------------------
    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
    ------------------------------



  • 15.  RE: Hamilton Grand Regulation

    Registered Piano Technician
    Posted 01-02-2018 11:24
    Undoubtedly. I had a client call me back once because I'd accidentally forgotten to completely tighten one of the action bracket screws. About 1/8 of a turn made the action feel different in that one section, and the hammers, aside from constant double striking, sounded brighter, but also more tinny. It was strange, and caused by only a small portion of the screw being out of place.

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



  • 16.  RE: Hamilton Grand Regulation

    Member
    Posted 01-02-2018 14:00
    Thanks for the various responses and some ideas. I will say that I have tried to compare some notes that work with closer letoff but I think it is a case of so many variables such as the poor state of the piano before it came to me. Somehow the piano played yet it barely had any punchings under the keys , hammers resting on the rails, worn letoff button felt. I think my plan going forward will be to identify the nest working note and the worst, swap the whippens and see if that isolates it as a whippen problem. Obviously I will need to look at other things such as the captan height, jack positioning, rep spring tension and action center friction. I have all of the sample hammers I sent and will try to swap some of those out - however I am fairly certain the angles and distances where accurately duplicated. This may be one of those instances of multiple causes throwing off the action from regulating. I keep hearing the little voice that says get it right once and duplicate it 87 more times

    ------------------------------
    James Kelly
    Pawleys Island SC
    843-325-4357
    ------------------------------



  • 17.  RE: Hamilton Grand Regulation

    Registered Piano Technician
    Posted 01-02-2018 15:27
    One more thought: you said there were no felts under the keys, and it played. Now that there are felts, the hammers won't let off close enough. What if you tried to raise the center rail by shimming with paper punchings or the like, which would raise the wippens and accordingly the hammers? I think it would work, but there are so many variables, such as assuming the repetitions are all the same, etc. Just one of those random thoughts.

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



  • 18.  RE: Hamilton Grand Regulation

    Registered Piano Technician
    Posted 01-03-2018 08:15
    Scott,

    Those blocks can mask bedding problems, so the owner might discover some new knocking sounds he hadn't heard in the past.  Also, the treble block usually serves as the stop for the una corda, which means that the action will now shift too far with the pedal.  And perhaps most importantly, those blocks maintain the strike point, which is critical in the treble; the piano owner now might find that he gets little or no sound out of the highest treble hammers.

    ------------------------------
    Kent Burnside, RPT
    Franklin TN
    615.430.0653
    ------------------------------