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Stubborn squeaky knuckles

  • 1.  Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-22-2014 23:08
    Hello everyone,

    I have had repeated callbacks for a new Ritmuller GH148R due to squeaky knuckles. At first I applied Teflon to all of the knuckles with a painter's brush. Then I thought that I probably missed some, so I reapplied to the ones that were squeaking again. Then I thought that I hadn't adequately burnished in the Teflon, so I did that. I just received another call saying that the squeak has returned. What am I missing?

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    Peter Stevenson RPT
    P.S. Piano Service
    Prince George BC
    250-562-5358
    ps@pspianoservice.com
    -------------------------------------------


  • 2.  RE: Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-22-2014 23:36
    Bruce

    My first inclination is to ask, are you sure it's the knuckles that are squealing?  

    But if you are sure, instead of teflon, take a pencil and apply a little graphite to the knuckle, and also to the top of the jack. 

    -------------------------------------------
    Willem "Wim" Blees, RPT
    Mililani, HI 96789
    -------------------------------------------


    Original Message


  • 3.  RE: Stubborn squeaky knuckles

    Posted 10-23-2014 00:27
    >
    > My first inclination is to ask, are you sure it's the knuckles that
    > are squealing?
    >
    > But if you are sure, instead of teflon, take a pencil and apply a
    > little graphite to the knuckle, and also to the top of the jack.
    >
    > My first inclination is to ask, are you sure it's the knuckles that
    > are squealing?
    >
    > But if you are sure, instead of teflon, take a pencil and apply a
    > little graphite to the knuckle, and also to the top of the jack.

    I'd recommend welders soapstone before I'd recommend graphite. But
    unless the knuckles are actually sticky, this sounds a tad fishy. Have
    you done a thorough shakedown and isolated it to the knuckled - for
    sure? I've seen balance rail holes make convincing knuckle squeak noises
    on casual inspection.
    Ron N


    Original Message


  • 4.  RE: Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-23-2014 00:42
    First of all, I do not know where the current squeak is coming from, as I haven't seen the piano since this last complaint.

    Regarding isolating the noise, now that I think about it, I may have only isolated wippen noise from key noise. This piano has had squeaky key bushings which I have also lubricated with Teflon. I think that the main reason why I was thinking that the knuckles were being stubborn was because each time I applied the Teflon to the knuckles, the squeak went away.

    I will try doing a more thorough shakedown when I return on Friday.


    -------------------------------------------
    Peter Stevenson RPT
    P.S. Piano Service
    Prince George BC
    250-562-5358
    ps@pspianoservice.com
    -------------------------------------------


    Original Message


  • 5.  RE: Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-23-2014 18:36
    Try the drop screw contact point.  Apply teflon to the leather that's at the tip of the wippon under the hammer rail. 
    These Pearl Rivers are notorious for having squeaks from that leather.  Working for the dealer, we'd have to remove the hammer rail to apply teflon to all those spots.  The leather drags slighting when it contacts the drop screw and causes a small squeak.

    -------------------------------------------
    Dave Foster
    Foster Piano Technology
    Waterford MI
    248-431-8804
    -------------------------------------------


    Original Message


  • 6.  RE: Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-24-2014 09:45
    Hi Peter,

    Try using your hand to resist the hammer's movement while pushing on the key.  This adds pressure to the whippen and knuckle.  It eliminates the rep lever spring and drop screw if the noise changes at all. 

    The Teflon may be drifting into the offending area as you apply it to the knuckles working only for a little while.

    Not knowing what type of rep lever spring you're working with I'll suggest moving the rep lever spring out of the notch to see if that affects the noise at all.

    Pressing down on the rep lever keeping the end of the lever from touching the drop screw while pressing the key would eliminate that one

    Damper lifter felt??  No problem, depress the sustain pedal during key activation.

    Whippen cushion?  Provide resistance or added weight on the whippen with a small screwdriver while depressing the key.

    In all these procedures listen for THE CHANGE.  It'll be obvious.

    Funny thing.  There must be something in the air lately.  I just tefloned a section of knuckles yesterday.
    -------------------------------------------
    Larry Fisher
    Owner, Chief Grunt, Head Hosehead
    Vancouver WA
    360-256-2999
    -------------------------------------------




  • 7.  RE: Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-24-2014 06:33
    Since you have already powered the knuckles,
    My guess would be the capstan cushions and or the balance rail bushings.
    -------------------------------------------
    Gerry
    Gerald P. Cousins, RPT ~ Director of Piano Service and Resources
    West Chester University of PA
    gcousins@wcupa.edu
    -------------------------------------------


    Original Message


  • 8.  RE: Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-24-2014 07:35
    I've also found squeaks at the bottom of the key at the balance rail hole.

    -------------------------------------------
    Paul T. Williams RPT
    Director of Piano Services
    School of Music
    813 Assembly St
    University of South Carolina
    Columbia, SC 29208
    pwilliams@mozart.sc.edu
    -------------------------------------------


    Original Message


  • 9.  RE: Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-23-2014 00:17
    Perhaps you are missing the source.  Lubricate the balancier leather under the drop screw with teflon powder using a thin felt mute to transfer the powder inserted between the drop screw and the balancier while depressing a group of them at once.  I have this occur frequently on Renner and other parts as well. The other possibilities are the repetition spring slot and the key bushings, especially the balance rail, for some reason.  

    -------------------------------------------
    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
    -------------------------------------------


    Original Message


  • 10.  RE: Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-23-2014 00:20
    btw, I don't recommend that you use graphite on the knuckles.  If the teflon doesn't solve the knuckle squeak then graphite certainly won't and it's probably not the knuckle.  You can spray the top of the jacks with TFL-50 but don't spray the knuckles themselves with that, the carrier seems to harden them.  

    -------------------------------------------
    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
    -------------------------------------------


    Original Message


  • 11.  RE: Stubborn squeaky knuckles

    Posted 10-24-2014 09:46

    Are you sure it's the knuckle? I frequently find it's the jack centre pin. In a grand there's also the rept. spring groove . . .  Michael (UK)
    -------------------------------------------
    Michael Gamble
    semi retired
    Brighton
    01273813612
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    Original Message


  • 12.  RE:Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-24-2014 10:58

    And yet, sometimes it's just a squeak in the knuckle that keeps coming back, So, what is our collective knowledge regarding the actual mechanism of knuckle squeaks?
    -------------------------------------------
    David Skolnik
    Hastings-on-Hudson NY
    914-231-7565
    -------------------------------------------



    Original Message


  • 13.  RE: Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-24-2014 18:48
    Thanks for all your input, everyone. It turns out that it was in fact the knuckle squeaking again. This time I brushed the knuckles with a brass brush, then relubricated with Teflon, then burnished with a piece of felt. I told her that if the squeak returns, I will contact the manufacturer, since this is not supposed to happen in a new piano. (The piano is actually three years old now, but squeaks have been coming up regularly since it was new).

    By the way, since I was listening intently for squeaks, I did find that some of the repetition lever springs were also squeaking, although very faintly, and mostly just as the hammer was coming up out of check.

    -------------------------------------------
    Peter Stevenson RPT
    P.S. Piano Service
    Prince George BC
    250-562-5358
    ps@pspianoservice.com
    -------------------------------------------


    Original Message


  • 14.  RE: Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-24-2014 22:39
    So here is the list of recommendations for dealing with knuckle squeaks from the posted responses (paraphrased):

    - apply Teflon to all of the knuckles with a painter's brush.
    - reapply to the ones that were squeaking
    - burnish in the Teflon,

    - use pencil to apply graphite to the knuckle and top of the jack

    - don't  use graphite on the knuckles.  If the teflon doesn't solve the knuckle squeak then graphite certainly won't
    - spray top of the jacks with TFL-50
    - don't spray the knuckles themselves, carrier seems to harden them

    - welders soapstone

    - suede brush knuckles

    - graphite on the repetition or jack top transfers to the knuckle;  tends to lead to stickiness of feel and eventually squeak. 
    - remove the existing material, then:
    - spray with Emralon/Permalon
    - brush with McLube 444 

    - Burnish the rep lever

    There seems to be some degree of variation or disagreement as to what should or should not be used as a lubricant, but it's not clear what is causing the squeak.  Besides the lubricant, variables are condition of wood; type and condition of knuckle covering (buckskin/ecsaine).  
     What IS the difference between the various discussed lubes?  lubricity, adhesion, durability
    - teflon powder
    - graphite
    - TFL-50
    - welder's soapstone
    - Emralon
    - Permalon
    - McLube

    Fred is correct about color of Emralon (green) and Permalon (white).  I'm unaware of of availability of emralon spray.  Permalon is available from Russell Products Co.  Cleveland. http://russprodco.com/Permalon.php


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    David Skolnik
    Hastings-on-Hudson NY
    914-231-7565
    -------------------------------------------


    Original Message


  • 15.  RE: Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-23-2014 08:39
    ...or if you like having fun, as I do, you can renew the wippen.  I am working on a 1923 Knabe that is being donated to a college.  A friend of min, and piano my teacher, runs the piano department so I want this piano to be as great as their $650 budget will allow.  After having the keytops replaced (because someone did a very bad job on the current plastic set), Cresendo punchings and a few other bits of felt here and there, I have $350 for my pocket for an over the top regulation.

    The graphite on the repetition lever has worn off over the years.  So I will take my denatured alcohol and take off the old from the lever and the jack and paint on and burnish new graphite.  Squeaky knuckles are not a problem now and when I'm done, I know they won't be for a very long time. I will also check to see if new felt is necessary for the lever's jack windows.

    The reason I renew is because I restore so much.  I work with pianos that you can't buy new parts for anywhere and I would rather keep the original parts anyway for reasons of historical preservation.  Of course on a more modern piano, most techs would get new parts before repinning, replacing felt pieces, and re-applying graphite. New parts are not in the college's budget and normally I would charge more, but some pianos you just give more of yourself to because there is much to be gained (student's pianos, other piano teacher's pianos, reputation among the areas big piano teachers). 

    I bet that you're going to find the real squeak somewhere other that the knuckles and jacks.

    -------------------------------------------
    Douglas Laing
    Tuner/Technician
    Safety Harbor FL
    727-539-9602
    -------------------------------------------


    Original Message


  • 16.  RE: Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-23-2014 09:27
    I've sometimes found the squeak to come from the capstan/heel interface.

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    Zeno Wood
    Brooklyn, NY
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  • 17.  RE: Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-23-2014 09:35
    This is true.  Basically anything that moves can squeek.  It's just a matter of search and destroy.

    Paul


    -------------------------------------------
    Paul T. Williams RPT
    Director of Piano Services
    School of Music
    813 Assembly St
    University of South Carolina
    Columbia, SC 29208
    pwilliams@mozart.sc.edu
    -------------------------------------------


    Original Message


  • 18.  RE: Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-23-2014 15:02
    I don't like graphite on the repetition or jack top. It always transfers to the knuckle (which happens quite quickly), and that tends to lead to stickiness of feel and eventually squeak. I have never had that problem with the Steinways with Emralon (green). Have had the problem with Renners, though (graphite). So if I were reconditioning wipps, I would remove the existing material, then either spray with Emralon/Permalon (if memory serves, Permalon is clear, Emralon green), or, more likely, brush with McLube 444 (I prefer brushing to spraying: less toxic fumes in the atmosphere).

    -------------------------------------------
    Fred Sturm
    University of New Mexico
    http://fredsturm.net
    "When I smell a flower, I don't think about how it was cultivated. I like to listen to music the same way." -Federico Mompou
    -------------------------------------------


    Original Message


  • 19.  RE: Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-23-2014 10:17

    Look at the drop screw leather. I had a situation recently that appeared to be the knuckles but was in fact a squeek coming from the drop screw connection point lubrication.

    Tim




    Original Message


  • 20.  RE: Stubborn squeaky knuckles

    Posted 10-23-2014 12:31
    I recently saw a piano from the Pearl River factory, about 5 years old, with action squeaks. The graphite on the repetition levers had worn off, leaving bare wood. I put Teflon powder on the knuckles, and ProLube on the jacks and reps. That was two months ago. Resurfacing the rep levers with a better lubricant may eventually be necessary. By the way, I also noted fine cracks beginning to develop in some of the natural key covers. ------------------------------------------- Ed Sutton Editor Piano Technicians Journal ed440@me.com 704-536-7926 -------------------------------------------
    Original Message


  • 21.  RE: Stubborn squeaky knuckles

    Registered Piano Technician
    Posted 10-23-2014 12:41
    Sometimes just a good suede brushing of the knuckles does wonders if that's where the squeak is. Knocks off the crusty surface.

    -------------------------------------------
    Paul T. Williams RPT
    Director of Piano Services
    School of Music
    813 Assembly St
    University of South Carolina
    Columbia, SC 29208
    pwilliams@mozart.sc.edu
    -------------------------------------------


    Original Message


  • 22.  RE: Stubborn squeaky knuckles

    Posted 10-23-2014 17:50
    Burnish the rep lever.

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    Regards,

    Jon Page