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Flange Bushings-Baldwin M1 Conservatory

  • 1.  Flange Bushings-Baldwin M1 Conservatory

    Posted 11-08-2018 13:30
    I have a client with a Baldwin M1 Conservatory Grand with the Accu-just hitch pins. Several of the hammers in the 4th and 5th octaves jam up due to cheating jacks so I pulled out the whippens and repinned both the jacks and rep levers . gram gauge showed readings from 2 grams to a high of 5 while the rep lever centers ranged from .5 to 2 grams.  It seems to me that the original bushing material and the quality control was poor I had to ream and trim felt out of most of the bushings and even a size 19 reamer pulled out felt.

    Several dampers have now started to act up coming down ever so slowly so I suspect the cause is the pinning/felt in the bushings of the damper underlevers and not in the damper guide wires or the damper guide rail bushings. we have had weird weather patterns all this summer and early fall and it has gone up to the 70's and 80's but 40's are predicted for the weekend. For now i am going to just apply some protek/clp to the damper flanges because owner is anxious to play the piano .  I am posting this to see if others have had similar experiences with these problems and what they did to effect a fix. The thought of repinning all of the other whippens makes me cringe but reading of .5 to 2 grams is not a good sign.


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    James Kelly
    Pawleys Island SC
    843-325-4357
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  • 2.  RE: Flange Bushings-Baldwin M1 Conservatory

    Posted 11-08-2018 15:36
    James

    If the piano is anywhere close to the ocean, you might want to consider installing a DC in the action cavity or at most, directly under the keybed or by the bellyrail as close to the back end of the action as possible. Most Baldwin action center problems I encounter in Hawaii are solved with a damp chaser keeping the action nice and toasty.

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    Willem "Wim" Blees, RPT
    Mililani, HI 96789
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  • 3.  RE: Flange Bushings-Baldwin M1 Conservatory

    Posted 11-08-2018 16:16
    So, 2 to 5 grams were the readings you got for jack centers? 2 should
    not be a problem, but 5 could be. And are we to surmise that the jacks
    with excessive friction in their action centers were cheating because
    they do not return rapidly enough, or at all?

    As for the repetition levers, .5 to 2 grams is definitely loose, and
    could contribute to a jack not returning promptly, due the the lesser
    amount of repetition spring tension. (The pinning of the hammer center
    also plays a parts in how strong the rep. springs are.)

    Would we be correct in assuming that you have already checked basics
    typically associated with cheating jacks such as inadequate rep.
    spring tension, jack position (vis a vis the knuckle) and repetition
    lever height?

    Alan

    On 11/8/18, Willem Blees via Piano Technicians Guild




  • 4.  RE: Flange Bushings-Baldwin M1 Conservatory

    Posted 11-08-2018 22:21
    I checked all of the items suggested like the rep lever height and knuckle alignment. The spring tension was also good but the weak pinning of the rep lever and tighter pinning at the jack were the main culprits. After repinning centers I had owner play all of the notes and they all played just fine. I am not 100 % sure that the bushing cloth was of the best quality or the glue was poor. According to the owner the piano was new in early 2000's so possibly the factory was experiencing problems with quality control and materials. I am hoping the problem does not surface on the remainder of the whippens. I guess time will tell. One possible red flag was the fact the piano had a dampp chaser on it already so maybe previous owner had been having action problems. Since this owner is not close to the ocean and the home is new as well as having new HVAC equipment a damp chaser may not be an absolute need. I will put a data logger in the piano and review the  graphs to see if there are variations throughout several 24 hour cycles.  Tomorrow the owner has two friends coming for a visit and both are professional pianists.
    Talk about getting thrown into the deep end of the pool...

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    James Kelly
    Pawleys Island SC
    843-325-4357
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