Pianotech

  • 1.  Wound trichord damping

    Registered Piano Technician
    Posted 01-25-2024 19:37

    Last May or June, a customer bought a rebuilt older Mason & Hamlin grand that faithfully duplicated the original wound trichords. The dampers worked fine here in California until the rainy season, but now not damping properly. Haven't seen it since the problem was reported, but I want to be prepared when I do. I know his preference will not be to refit with bichords, but what suggestions do folks have for trichord dampers that work well and long term. Or is it even possible to get the existing dampers to work? Thanks for your thoughts.



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    Paul Larudee RPT
    El Cerrito CA
    (510) 418-4485
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  • 2.  RE: Wound trichord damping

    Registered Piano Technician
    Posted 01-25-2024 20:55
    One suggestion I learned from LaRoy was to deepen the cut of the trichord. Just take a sharp knife and cut the middle groove of the damper.

    Sent from my iPhone




  • 3.  RE: Wound trichord damping

    Registered Piano Technician
    Posted 01-25-2024 21:22
    Thanks, Wim that's worth a try. I'll have some felt at the ready in case it doesn't work, but any suggestions for what replacement felt to use?






  • 4.  RE: Wound trichord damping

    Posted 01-25-2024 21:29

    what Wim suggested, has worked for me in most cases!

    Peter



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    Peter Janssen
    Fort Myers FL
    (678) 416-8055
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  • 5.  RE: Wound trichord damping

    Registered Piano Technician
    Posted 01-25-2024 21:39

    If it was working in the dry season, it seems the symptom has more to do with bushings than the damper felt.



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    Steven Rosenthal RPT
    Honolulu HI
    (808) 521-7129
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  • 6.  RE: Wound trichord damping

    Registered Piano Technician
    Posted 01-27-2024 02:05
      |   view attached
    Assuming the regulation and adjustment is good and, yes, the cut is deep enough, this is probably a mass problem. Especially if the damper head is offset. 

    ddf






  • 7.  RE: Wound trichord damping

    Registered Piano Technician
    Posted 01-27-2024 02:33
    Thanks, Del,

    It seems clear it's not just one thing, else why would it appear with the change in the weather, and not just one damper. I'm certainly considering adding weights, if all else fails. But if all else fails,  the best solution is probably to convert the wound trichords to bichords, if the customer is willing. I'll know more on Monday.






  • 8.  RE: Wound trichord damping

    Registered Piano Technician
    Posted 01-27-2024 08:09

    In addition to slicing the center higher I always insert a piece of cord (ala Steinway) up in the crevice. This prevents the fingers of felt from closing in on the center string and possibly neglecting the outer strings. I have rarely had a problem. I have long used the felt that Schaff sells (Laroux? or something like that). Different profiles for different situations but the process is always the same.

    Edit: It's also important to test each offending note to see if there is some sort of pattern going on (e.g. right string only singing, left string, etc.). Possible that the guide rail has moved. Unlevel strings can raise havoc as well.  Must accurately determine the cause before proposing a solution. 

    Peter Grey Piano Doctor 



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    Peter Grey
    Stratham NH
    (603) 686-2395
    pianodoctor57@gmail.com
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  • 9.  RE: Wound trichord damping

    Registered Piano Technician
    Posted 01-30-2024 18:30
    Thanks to everyone. I came prepared to the appointment prepared for all contingencies, but it turned out not to be pampers at all, rather a broken sostenuto dowel that was interfering with the dampers. That's OK, at least I'm prepared for the next time, when it occurs.

    Paul





  • 10.  RE: Wound trichord damping

    Registered Piano Technician
    Posted 01-30-2024 23:22

    Go figure it would be right in the section with the most finicky dampers! Thanks for sharing the result, Paul :)



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    Nathan Monteleone RPT
    Fort Worth TX
    (817) 675-9494
    nbmont@gmail.com
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