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Henry F. Miller Grand Piano

  • 1.  Henry F. Miller Grand Piano

    Registered Piano Technician
    Posted 03-24-2020 13:39
    Hi, everyone. I have a head scratcher to deal with during this enforced break from university work (on campus, anyway).  The subject is an older (#52094) Henry F. Miller grand that is in a voice professor's studio.  The staff accompanist that plays it has continually complained that the thing is "clunky", and "plays like a truck" " Awful"  "I hate it!!"  are his comments.  I have been looking at it and scratching my head.  Attached are some pictures of the #88 hammer, shank.
    ​    In checking the measurements of some rudimentary action parameters, some things stick out to me.  The hammer is bored too long by like 1/4 inch from what the string height-center pin distance should be, with no rake.  The shank shows an area below the hammer that suggests that these hammers were added to old shanks, and hung at a greater hanging distance than previous.  And yet the strike point grooves are pretty much in line with where a proper centering should be (not over or under centering).  The shanks have a 17 MM knuckle distance, with an 11 MM knuckle size.
        Things I noted in measuring (I can't find where I put the previous measurements, but I remember that none of the things are radically out of line with what is considered "normal"). were the dip is about 10mm,  let off and all that is pretty normal,  key ratio is pretty good.  The only thing that I might want to mess with is the overall action ratio is a little on the high side, closer to a high 5's or 6 to 1 (Dale Erwin device).
       I am tempted to just taper and tail the hammers (trim the weight), and see what happens, but I am perplexed by the pictures and possible scenarios of how and why that happened.  I know that in the 80's, it was kind of in vogue to put these big, massive hammers on because they made this big tone, and I have seen this on some other pianos at the university that he dealt with years ago.  I  spent many hours on a Steinway A, to make it playable about a year ago.  Any thoughts would be appreciated.

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    Clark Sprague
    Bowling Green OH
    419-352-2198
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  • 2.  RE: Henry F. Miller Grand Piano

    Registered Piano Technician
    Posted 03-25-2020 04:18
    Before you start chopping on the hammers try switching a few hammers and shanks with higher, smaller hammers from up the scale and see if that is the answer.

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    Blaine Hebert
    Duarte CA
    626-795-5170
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  • 3.  RE: Henry F. Miller Grand Piano

    Registered Piano Technician
    Posted 03-25-2020 10:33
    The clean area might just be where the last tech cleaned off the old glue.  Here are a couple questions:
    What is the down weight of a few samples?
    What is the friction?  Down weight-up weight/2
    How flat are the knuckles?
    When do the dampers lift?

    Stewart Freedman

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    Stewart Freedman
    Akron OH
    330-376-3373
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  • 4.  RE: Henry F. Miller Grand Piano

    Registered Piano Technician
    Posted 03-25-2020 12:34
    Thank you for all the replies!.  I did find the few rudimentary measurements that I took back in October.  I noted that middle C (note 40) had a 9.7g SW, 17 MM knuckle distance, a 6.0/1 overall action ratio, 11MM knuckle diameter.  113MM action spread.  G3 (note 35) had a 66G DW and I didn't measure the upweight.  There were a lot of notes especially lower than middle C, that had over my full stack of cheap gram weights for
    DW.  I only have a basic set of weights, and a full stack is 70.7G, so it's pretty awful.
        I have started the process of tailing, tapering, and re-shaping, and will take some weights of a few hammers before and after.  I can see that the tailing only shaves off about  2/10 of a gram, so we will see where that all goes before changing other parameters.  Thanks for all the advice!  Stay well.     Clark

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    Clark Sprague
    Bowling Green OH
    419-352-2198
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  • 5.  RE: Henry F. Miller Grand Piano

    Posted 03-25-2020 13:57
    Check to see if you have too much aftertouch. If so, plug the hammers and bore to the proper distance. I would think with that much work you should get some new hammers.
    Dale Erwin's device measures action ratio by distance. It's an average. You need to see if the action ratio changes as the key is played. Use some weights and watch the changes in lift. If the hammer doesn't move from the rest position until you pound on the table and then accelerates up to drop, try regulating the hammer shank to the position it would be if you had correct bore distance. Having the wippen and shank in too low of a start position might give a heavy feel to start and then a loss of feel because energy required to start the hammer leaves the player with a loss of control through the keystroke.
    To seriously measure the changing action ration, you would remove the hammer and balance the note to zero out, then hang a weighed hammer and check to see what makes it lift and what weight makes carry through the keystroke.
    Too much trouble in my opinion,, you can intuitively see the action ratio and friction when you watch the action. The lack of movement at the start of the stroke could be excessive friction because of regulation required for the bore distance being wrong.
    There are lots of ways to approach this problem and it is a common one. I would be interested to hear how it turns out

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    Keith Roberts
    owner
    Hathaway Pines CA
    209-770-4312
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