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Baldwin Hamilton - one "string" drops suddenly in pitch, but not on test blows

  • 1.  Baldwin Hamilton - one "string" drops suddenly in pitch, but not on test blows

    Registered Piano Technician
    Posted 10-09-2019 00:28
    I am calling this piano a Baldwin Hamilton because that's what I know it as. Label is Baldwin, but I've always thought of the "flip top" studio pianos (with built in lid prop) as Baldwin Hamilton.

    Anyway, I tuned this piano once 3 years ago, did 30-50 cent pitch raise, no issues. However at that time no one was really playing the piano. Now the owner is taking lessons and practicing every day.

    Tuned the piano 2 weeks ago and almost immediately the owner emailed me to say one note was very out of tune. I was out of town then but went to see the piano the day I returned (2 days ago) and one "string" of the three strings on the F# just before the treble break had dropped VERY noticeably. I thought maybe I had committed some terrible oversight and left it that way when I tuned it but owner said it was perfectly in tune when she first sat down to play it, but quickly went out of tune.

    Weird. Piano is in perfect like-new condition. Hammers barely worn, tuning pins SUPER tight like a new piano. I am extremely rigorous with test blows. (Passed my PTG tuning exam at over 90% with entirely aural tuning back in the '80s.)

    So I pulled up the middle string, whacked it hard with a bunch of test blows. Nothing changed, and I told the owner I had no idea what had caused the string to drop and that I have never encountered this before (which is true). I had no theory, but told her to let me know if it happened again. She texted me that night and said the note went out of tune shortly after I left.

    The owner is a woman of about my age (73) and is the only one playing the piano. She is definitely not a pounder, plus I DID pound it and nothing happened!

    Went back yesterday. Only possible thing I could think of was that no matter how hard I pounded my test blows, the string was getting "hung up" with friction somewhere. The weird thing is, why only on that half of the wire? The middle "string" is the same wire as the right "string", but right string is unaffected!

    On that theory (friction somewhere along the string) I took the action out to see if there was any obvious problem (no), dropped a little ProLube at all the bearing points. In doing so I noticed that at the hitch pin end, the strings all rise up sharply from the hitch pin and run across a sort of high bearing point on the plate - a  plate that is not smooth but very bumpy/rough finish - before reaching the bridge. Also, each hitch pin goes thru a hole in the plate and it seems to me the string kind of gets pulled around the hitch pin and down into the recess of the hole - an opportunity for a lot of the string to bind. Put lube there too.

    Then pulled up the string, set the pin, pounded like crazy. Told her if it happened again, I would post it to the forum.

    She texted me and said she sat down to practice and about 15 minutes after I left the string dropped again.

    My next attempt at a solution will be to replace the string. And lube all bearing points before putting the string on.

    But before I do that, maybe there is an Baldwin dealer of yore out there who has encountered this kind of thing who can offer advice. I used to do warranty and warehouse tunings for Baldwin in Chicago in the '80s, so it's not like I never tuned a Baldwin piano.

    Any other suggestions?

    Barb

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    Barbara Barasa
    Ashland OR
    541-552-9349
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  • 2.  RE: Baldwin Hamilton - one "string" drops suddenly in pitch, but not on test blows

    Registered Piano Technician
    Posted 10-09-2019 01:23
    Barb

    Your explanation of what's going on at the hitch pin might be the cause of the problem.  It sounds like the string is not down in the plate at the hitch pin.  With a brass rod of some sort tap the string down on both sides of the hitch pin.

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    Willem "Wim" Blees, RPT
    Mililani, HI 96789
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  • 3.  RE: Baldwin Hamilton - one "string" drops suddenly in pitch, but not on test blows

    Registered Piano Technician
    Posted 10-09-2019 02:10
    I'm think that there's a crack in plate - probably in the strut next to the note in question. I have a Kawai that does the same thing. I pointed it out to the owners, and they are fine with it now, because they understand that it's the piano, not me.

    Next time you're there, check it over for a crack and let us know. Best of luck,

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    Benjamin Sanchez, RPT
    Piano Technician / Artisan
    (805) 315-8050
    www.professional-piano-services.com
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  • 4.  RE: Baldwin Hamilton - one "string" drops suddenly in pitch, but not on test blows

    Member
    Posted 10-09-2019 07:00
    There might be a weak spot in that length of wire and it's getting ready to break. The coil might not be tight around the pin. Use parallel pliers to squeeze in the becket and rotate while squeezing counter-clockwise a quarter turn or so to coax the wire around the pin; four times. The tension can drop anywhere from 10c to a minor third.

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    Regards,

    Jon Page
    mailto:jonpage@pianocapecod.com
    http://www.pianocapecod.com
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  • 5.  RE: Baldwin Hamilton - one "string" drops suddenly in pitch, but not on test blows

    Registered Piano Technician
    Posted 10-09-2019 07:07
    I would say it is what Jon Page has said, or that the becket is slipping out of the tuning pin.

    I.e., during installation, it was only part way through the hole. You won't be able to see this while the string is under tension. Everything looks normal, and it seems to tune OK with test blows. Then it slips out, and goes wildly out of tune.

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    John Formsma, RPT
    New Albany MS
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