Pianotech

  • 1.  Chinese Hammer Flanges

    Posted 02-17-2019 08:42
    A customer has a Chinese Christofori console. It has all kinds off loose/tight hammer flanges. I reamed the tight ones last year and got it playing, but now more are stuck with some pins working out of the flanges. I plan to offer to re-bush all the flanges. Does that seem the best solution, or is there some design flaw I should know? I guess the other option is to replace them with better-quality parts.

    ------------------------------
    Philip Jamison
    Philip Jamison Pianos
    WEST CHESTER PA
    610-696-8449
    ------------------------------


  • 2.  RE: Chinese Hammer Flanges

    Registered Piano Technician
    Posted 02-17-2019 08:58
    Hi Philip:
    My experience with Chinese flanges is that the felt is quite susceptible to swelling when there's moisture. Then, the wood is quite spongy, so it too changes with humidity. The ones you reamed are likely to still have problems unless you pinned them on the loose side. You might try rebushing some just to see what happens. I'd make sure to size them afterwards with alcohol/water or whatever to make the fibers in the bushing cloth more densely packed and solid. If you can get better quality flanges, that's good. But then you'll have some issues with alignment/traveling afterwards.
    Good luck,
    Paul McCloud


    Philip Jamison
    A customer has a Chinese Christofori console. It has all kinds off loose/tight hammer flanges. I reamed the tight ones last year and got it playing, but now more are stuck with some pins working out of the flanges. I plan to offer to re-bush all the flanges. Does that seem the best solution, or is there some design flaw I should know? I guess the other option is to replace them with better-quality parts.

    ------------------------------
    Philip Jamison
    Philip Jamison Pianos
    WEST CHESTER PA
    610-696-8449





  • 3.  RE: Chinese Hammer Flanges

    Member
    Posted 02-17-2019 09:42
    i have worked on two of these pianos and not seen the problem you are describing. one was moved here from maryland and has a full dampp chaser system in it so it has been in cold and now more humid situations. what paul has stated about exposure to humidity changes and the way the cloth and wood behaves explains your situation. the second piano is on the ground level of a raised beach home in a finished play area. year round there is higher humidity that would tend to keep things from shrinking and getting loose. you may want to suggest putting a full dampp chaser in to stabilize things. if you repin every action center it will take a huge effort.

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



  • 4.  RE: Chinese Hammer Flanges

    Member
    Posted 02-17-2019 09:51
    how old is this piano and under what environmental situation is it in ? fireplace or wood stove ? is the humidity
    high in summer or when you are there ? 

    the cost of new parts and your time/labor may not be economically feasible. if its that bad and new maybe you have a warranty issue. it may also be better to get a replacement piano. the scenario is like the flaking center pin problem in which you fix some flanges and more surface. it is not a bad idea to purchase a data logger and leave it in the piano for two weeks or more. this way you have proof that the piano is in a bad or good environment since you get 24 x 7 readings on graphs.

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