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Kawai RX-2 damper guide rail

  • 1.  Kawai RX-2 damper guide rail

    Posted 02-06-2023 03:57
    I service a Kawai RX-2 #2569531​ c2007 with tight damper guide rail bushings. Is this widespread or just this piano I've ironed and lubed and I'm considering Profelt or rebushing. Wisdom, please.

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    James Baker RPT
    Matthews NC
    (704) 517-6674
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  • 2.  RE: Kawai RX-2 damper guide rail

    Registered Piano Technician
    Posted 02-06-2023 04:44
    James, 

    I faced the same problem on a Boston Grand, manufactured by Kawai. Made a list, as usual, from simplest/least expensive/least intrusive to most. First item on the list was VS Profelt on the damper guide rail bushings. Expect the bushings to possibly get tighter at first, but to eventually behave themselves. May need overnight for it to come around.

    One would not find this response to my query archived as it was sent to me as a private message.

    Please let us know how this turns out!

    Best, 

    Alan

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    Alan Eder, RPT
    Herb Alpert School of Music
    California Institute of the Arts
    Valencia, CA
    661.904.6483
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    Original Message


  • 3.  RE: Kawai RX-2 damper guide rail

    Posted 02-06-2023 05:08
    Thank you, VS Profelt was my next choice, I wanted some moral support.



    Original Message


  • 4.  RE: Kawai RX-2 damper guide rail

    Member
    Posted 02-06-2023 09:05
    I would try several things. Check the pinning on the damper flange - ask me how I know

     remove a few dampers- clean, polish and lubricate the damper wires and add some teflon to the bushings . reassemble and test . If glue was used to hold the bushings in place it could be interfering with the wire

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    James Kelly
    Owner- Fur Elise Piano Service
    Pawleys Island SC
    (843) 325-4357
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    Original Message


  • 5.  RE: Kawai RX-2 damper guide rail

    Posted 02-06-2023 09:53
    In many instances it could be seasonal shifting due to dramatic humidity changes or dramatic pitch change. If it the case - gides screws release and pry gides to the side , then tight the screws

    Alexander Brusilovsky


    Original Message


  • 6.  RE: Kawai RX-2 damper guide rail

    Posted 02-06-2023 12:24
    I will check the guide rail position, thanks.



    Original Message


  • 7.  RE: Kawai RX-2 damper guide rail

    Posted 02-06-2023 12:23
    I should have mentioned that I did check the mechanics. You can hear the bushing rubbing the wire after the damper felt clears. Thank you though I bear watching. 



    Original Message


  • 8.  RE: Kawai RX-2 damper guide rail

    Registered Piano Technician
    Posted 02-06-2023 13:17
    I ran into this issue on a 10 year old Cable Nelson CN151.  I drilled a hole in an inch long piece of 1/4 inch brass cylindrical stock, and poounded in an appropriately sized bridge pin.  This I inserted as a caul into the temperature controlled soldering iron I use for ironing key bushings.  I removed the dampers, ironed the damper guide rail bushings, and lubed the bushings with TFL-50 dry lube and the damper wires with pro-lube.  That was a couple of years ago, and everything is still behaving well.

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    Floyd Gadd RPT
    Regina SK
    (306) 502-9103
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    Original Message


  • 9.  RE: Kawai RX-2 damper guide rail

    Posted 02-06-2023 20:09
    All I had with me was my capstan tool and a lighter. It worked, but I don't think it will last. The soldering iron would be better. I'm going to try VS Profelt and I'll report later.



    Original Message


  • 10.  RE: Kawai RX-2 damper guide rail

    Registered Piano Technician
    Posted 02-07-2023 09:43
    Hi James,
    If the piano was fine In the summer, why would there be this problem now?  If it's always been like this fine.  Go your route.  

    I think if the piano has dried some from heating season there are two more things;
    The key leads can move out and bind on the next damper lever.  
    The dryness can cause loss of height in the sounding board and dimension change in other wood.  In this case you are probably looking at more pressure on the wire from the guide bushings on the bass side of wire.  I've also found that sometimes the guide rail screws through the SB  can be loose from wood shrinkage.  There can also be damper timing issues from such drying. 
    Good luck
    Jessica Masse 
    RPT
    --
    Sent from Gmail Mobile



    Original Message


  • 11.  RE: Kawai RX-2 damper guide rail

    Posted 02-07-2023 16:01
    More good things to check, thank you. I'll let the list know what turns up.



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  • 12.  RE: Kawai RX-2 damper guide rail

    Registered Piano Technician
    Posted 02-07-2023 16:18

    I what you say about hearing a rubbing sound, this indicates oxidation of the damper wires.

     

    It's a hassle, but the best solution is to polish the wires.  Burnish the bushings before reinstalling the dampers.

     

    Don Mannino




    Original Message


  • 13.  RE: Kawai RX-2 damper guide rail

    Posted 02-07-2023 16:57
    I'll do that. Is this only this piano or was there ever a problem with this.



    Original Message


  • 14.  RE: Kawai RX-2 damper guide rail

    Member
    Posted 02-07-2023 21:11
    Karen Robinson did a great class on grand dampers and I believe you can find it in the PTG Journal. One thing I recall is the importance of the alignment of the wire to the damper head from the damper flange. If it is not straight you get lots of side friction even if the hole in the bushing is large. Oxidation on the wire as Don points out can hang the damper up so I would clean and polish all of the wires even if it is a hassle. By the time you are done they should play like greased lightening.

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    James Kelly
    Owner- Fur Elise Piano Service
    Pawleys Island SC
    (843) 325-4357
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    Original Message


  • 15.  RE: Kawai RX-2 damper guide rail

    Registered Piano Technician
    Posted 02-08-2023 11:56
    James Baker,

    There is no special trend here - oxidation of the plating can happen with any damper wire.  But this combined with the tight bushing fit seems to point to humidity issues at this location.

    Do ease the bushings as well, and pay attention to the wire bends as well as James Kelly pointed out.   Withe the action out you can lift the dampers one by one with your finger and feel the drag on the wires.

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    Don Mannino RPT
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    Original Message