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Regluing Loose Hammerheads

  • 1.  Regluing Loose Hammerheads

    Posted 08-15-2023 10:39

    I have a customer (church) with a 1960 Kawai no. 750 (7'4"). It is generally is so-so ok-ish shape for a 63 year old piano. Pianist complained about action noise - clicking. Hammers in the reported clicking range (about E4 through E6) are loose. I don't think the church wants to spend much money on this piano at this time.

    I'm looking for a quick/cheap way to address the loose hammer heads. What is the latest on quick regluing of hammers - thin CA - just a drop or two and let it wick its way in (align first, of course!)?

    My thinking was to just reglue the hammers and see how the action sounds. I won't be surprised if the pianist is happy with that improvement. However, the entire action makes a good bit of noise - mostly when a key is released. This piano has whipped assist springs. I don't have much experience with them. The springs hold the whippens up when a hammer is raised. Is that normal (I'm guessing, yes)? There is a clunk when the whippen heel hits the capstan and when the knuckle hits the repetition lever. Is there anything that can be done to reduce that noise short of replacing knuckles and whippen heel cloth?



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    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
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  • 2.  RE: Regluing Loose Hammerheads

    Registered Piano Technician
    Posted 08-15-2023 11:50
    Hi Terrance

    CA glue works great on the hammer heads.  
    A suede brush or soft brass brush on the knuckles will soften them up.
    Put the action upside down and brush the wippen heels and also "voice" them by putting the voicing needles into the sides of the cushion. 
    You can also clean and brush the back rail cloth.

    But you must realize that all of that is a temporary solution to a long-term problem. This is a heavily used 64-year-old piano that needs to have all the action parts replaced. Sooner or later, if the church wants this piano to serve them for a long time in the future, they're going to have to spend some money on it. The other option is to get one of their parishioners to step up and buy a new one. 

    Wim





  • 3.  RE: Regluing Loose Hammerheads

    Registered Piano Technician
    Posted 08-15-2023 23:51

    Hi Terry,

    I don't use CA glue for hammers. I want something reversible. This job can be done very quickly and efficiently with TiteBond Quick-N-Thick. I get a drop on my finger and apply it to the hammerhead where it touches the shank, then repeat on the next one. When it dries the clicking's gone. Doing the whole set usually only takes half an hour or so, and the piano's ready to be tuned by the time you're done. Good luck!



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    Benjamin Sanchez, RPT
    Piano Technician / Artisan
    (256) 947-9999
    www.professional-piano-services.com
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  • 4.  RE: Regluing Loose Hammerheads

    Posted 08-16-2023 09:50

    Benjamin S. wrote: "I get a drop on my finger and apply it to the hammerhead where it touches the shank"

    Where it touches the shank? Exactly where is that? On the cut shank side of the hammer moulding or the side where the shank enters the hammer moulding? Seems like it would be difficult to get the glue into the joint like that.



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    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
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    Original Message


  • 5.  RE: Regluing Loose Hammerheads

    Registered Piano Technician
    Posted 08-16-2023 16:38

    Hi Terry,

    Sorry, I should have been a little more specific. I apply the glue where the shank enters the hammer molding. The idea is to essentially reinforce the glue collar. The glue is thin enough that it will work into whatever crack there is and seal it up, and your finger helps to get it in there. I've been using this method for years and haven't seen negative side effects. Of course, if the original glue collar is gone or disintegrated, you'll need to form a new one properly. But often the hammer will start clicking long before that point, which is where this method comes in. 



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    Benjamin Sanchez, RPT
    Piano Technician / Artisan
    (256) 947-9999
    www.professional-piano-services.com
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    Original Message


  • 6.  RE: Regluing Loose Hammerheads

    Registered Piano Technician
    Posted 08-17-2023 01:51
    For me the easiest and best is a couple of drops of thin CA glue. I rotate the hammer up so it is straight up. Put the drops on edge of the shank. Gravity will pull it into the space. Don’t use accelerator to let it work itself in. Always ends the click. The hammer stays in its alignment. Taking the hammer off and regluing leaves room for mis-alignment.

    Sent from my iPad
    CarlPianoTech.com


    Original Message


  • 7.  RE: Regluing Loose Hammerheads

    Posted 08-17-2023 12:18

    I have to wonder if any of those glues mentioned will work with Baldwin grands that have the clear brittle glue. Usually I have to remove the hammer which (is usually doable by hand) and scrape that glue off (sometimes with a shank reducer). I might try one of these methods to save a lot of work. I wonder if anyone has used this method on the type of clear briddle glue I mentioned



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    Randy Prentice RPT
    Tucson AZ
    (520) 749-3788
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    Original Message


  • 8.  RE: Regluing Loose Hammerheads

    Registered Piano Technician
    Posted 08-16-2023 02:07

    Terry,

    When I have one or a few loose hammers I extract the hammers and reglue, usually with Titebond. When I have more than a few I dillute Titebond (or Elmers) with water and apply to the joints with a dropper. On some occasions I have used a thin hide glue with good success.  I perfer this to CA glue myself - not trying to be a Luddite, I just have had better luck with dilluted glues and they are easier to clean up.



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    Blaine Hebert RPT
    Duarte CA
    (626) 795-5170
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  • 9.  RE: Regluing Loose Hammerheads

    Registered Piano Technician
    Posted 08-17-2023 11:49
    I second Blaine’s approach, I have not had the best luck with CA for a lasting repair (and easy to drip down the tail and create a slick surface that doesn’t catch so well on the back check.)

    Joe Wiencek


    Original Message


  • 10.  RE: Regluing Loose Hammerheads

    Registered Piano Technician
    Posted 08-17-2023 12:05

    I also cast my vote for thin CA. CA actually has a relatively weak shear strength so you can still extract the head later if they need to be replaced. Just rotate the hammers all the way up and put a drop right on the top of the shank where it is cut. Thin CA glue is so penetrating, it should go right into the joint. Carl was spot on: don't bother with accelerator. It will just seal the top and if you needed to add some later it might prevent it from penetrating. 

    As far as noisy actions go, I have found it can be a combination of several areas where old felt gets hard and noisy: Back rail cloth, knuckles, wippen cushions, key bushings, worn balance holes, even felt on the jack regulating button. I've had some moderate success going through and brushing/needling these areas. It's always a good idea to pick one of the noisiest notes and see if you can get that one to quiet down. You might discover what the hierarchy of noise is and where most of the improvement can come from. 



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    Ryan Sowers RPT
    Olympia WA
    (360) 480-5648
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    Original Message


  • 11.  RE: Regluing Loose Hammerheads

    Registered Piano Technician
    Posted 08-18-2023 10:37

    Issac Sadigursky suggested simply dripping a little vinegar into the joint to reactivate the glue. 



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    Scott Cole, RPT
    rvpianotuner.com
    Talent, OR
    (541-601-9033
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  • 12.  RE: Regluing Loose Hammerheads

    Registered Piano Technician
    Posted 08-18-2023 11:16
    Scott

    That was the “old” method, before CA glue, when most hammers were glued with hide glue. But I’m not sure if vinegar has any effect on some of the new glues used now.

    Wim.

    Sent from my iPhone


    Original Message


  • 13.  RE: Regluing Loose Hammerheads

    Posted 08-18-2023 11:34
    Vinegar in this case only increases penetrating ability for the water. Water , what reactivates the glue. And only if glue is water soluble, like hide glue. In case of Polyvinyl acetate glues ( white, yellow, carpenter glue) improving will be , but only temporarily. Wood will swell but it will dry and clicking could be worse.

    Alexander Brusilovsky


    Original Message


  • 14.  RE: Regluing Loose Hammerheads

    Registered Piano Technician
    Posted 08-18-2023 11:40

    Also, reactivating the old glue only works provided the glue joint was not starved to begin with.

    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


  • 15.  RE: Regluing Loose Hammerheads

    Registered Piano Technician
    Posted 08-19-2023 03:04

    I suspect that the vinegar was simply expanding the wood and temporarily eliminating the loose joint, which would quickly dry out and click more.

    Vinegar is useful for softening PVA glue and Titebond, but I wouldn't use it for a hide glue joint when thinned out hide glue would work much, much better.



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    Blaine Hebert RPT
    Duarte CA
    (626) 795-5170
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    Original Message