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Regluing separated hammer felt

  • 1.  Regluing separated hammer felt

    Member
    Posted 08-22-2021 15:37
    I live in Hawaii where the hammer felt on some pianos lifts of the wood core.  This happens primarily on Baldwin pianos.  I've also seen it happen on several sets of Renner Blue hammers.  Some of these pianos have 40-60 hammers that need to be reglued.  The high treble is least likely to separate.  The bass hammers are most likely and can be very difficult to reglue.

    I've tried different methods of gluing and clamping to fix the problem.  I've yet to find a method that works very well without being overly labor intensive.  I wonder what has worked best for some of you who have dealt with this.

    I get good results with superglue,  The challenge is to get the felt clamped down evenly and fully with no gaps.  I saw a Journal article years ago on this topic that showed a particular clamp that was able to conform well to the shoulders to get a good tight glue joint, but I haven't been able to find that article again.  Can anyone recommend the best type of clamp (and where to buy) and the most efficient method for doing the job?

    Please don't bother to suggest putting on a new set of hammers.  I'm talking mainly about Baldwin console pianos worth around $500 where the clients (and I) just want to save the piano from the dump.

    Looking forward to hearing from techs who have experience with this problem.

    Thanks,
    Tim Jasnau



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  • 2.  RE: Regluing separated hammer felt

    Registered Piano Technician
    Posted 08-22-2021 15:53
    Hi Tim

    I ran accross this all the time. But I heard it's not a problem on all Baldwin products made 20 - 40 years ago not just in Hawaii, but all over the country.

    Usually when I get a spinet with that many hammers loose, I condemn the piano. If the customer is committed to keeping the piano, I recommend a new set of hammers. 

    But if you're up to it, and the customer is willing to pay to have the work done, take the action out and put it on your bench. I use CA glue and needle nose vice grips. Put the glue on the wood, kick it, and then clamp on the vice grips. If you've got more than one set of vice grips, you can do multiple hammers. But if you only have one, the glue usually sets up in less than 5 minutes. 

    The main problem is that there might only be 20 - 40 loose now, but you can bet your bottom dollar that the rest will come loose sooner or later. So in addition to clamping the ones that have come off, when you get done with those, put the action on one end, and run a bead of thin or medium viscosity CA glue along the felt and molding on each hammer. Then turn the action over and do the same thing to the other side of each hammer. 

    Try not to get the glue too far towards the crown of the hammer. It's not necessary, but it will also harden the hammer, and give it a much better tone. But you don't to over do it. 

    Good luck. 

    Wim





  • 3.  RE: Regluing separated hammer felt

    Posted 08-22-2021 17:13
    Two-glue method. A thin layer of white glue on the felt and Thick CA on the molding.  Dry fit first so the Vise-Grip/clamp is ready to go and you can clamp it in one motion.

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    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
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  • 4.  RE: Regluing separated hammer felt

    Member
    Posted 08-22-2021 19:23
    What I'm mostly looking for help with is the clamping method.  Vise grips work, but because of the shape (and varying size) of the hammers, it's hard to get a tight glue joint with no gaps.  I've been searching for the best clamping system, where I can glue/clamp every other one and move on quickly to the next.  Vise grips are heavy, especially if I want to glue up half of the hammers at a time.  The best looking clamp I've found online for the job is out of stock on Amazon and I haven't yet found where they are available.  Task Tools T74210 - 6 1/4" ratcheting clamp -



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    Tim Jasnau
    Makawao HI
    808-633-6655
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  • 5.  RE: Regluing separated hammer felt

    Registered Piano Technician
    Posted 08-22-2021 21:10
    Tim

    Schaff sells a ivory key clamp, part 251, that will work. It might be a little difficult to use on bass hammers, but will work on the rest of them

    Wim



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    Willem "Wim" Blees, RPT
    St. Augustine, FL 32095
    Tnrwim@aol.com
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  • 6.  RE: Regluing separated hammer felt

    Registered Piano Technician
    Posted 08-23-2021 00:39
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  • 7.  RE: Regluing separated hammer felt

    Registered Piano Technician
    Posted 08-23-2021 00:42
    Tim -
    I've been trying to send you a link to a different item but apparently I've been doing something wrong, so I'll just tell you:
    take a look at Irwin brand Quick-Grip clamps 1 1/2" or 2".  Amazon has them.
    Also, contact Ken Eschete at Bentside Arts.  He has some creative jigs for this purpose.

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    David Skolnik [RPT]
    Hastings-on-Hudson NY
    917-589-2625
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  • 8.  RE: Regluing separated hammer felt

    Registered Piano Technician
    Posted 08-22-2021 23:44
    I've never had to do more than a couple at a time so the method I use may be one of those it-works-in-a-pinch methods. Though I have read a couple of articles on the preferred way to do the method I use. Which is: Glue the hammer back in place using Tightbond white glue and then wrap the glued hammer with thread. Lightly coat the wrapped thread with a little white glue to make sure it doesn't go anywhere and the thread wrap will act as a permanent vice. That hammer will never come off again. Tightbond sets pretty quickly so the hammer is ready to play again within minutes. Very much the same principle as repairing a broken hammer shank.

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    Geoff Sykes, RPT
    Los Angeles CA
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  • 9.  RE: Regluing separated hammer felt

    Registered Piano Technician
    Posted 08-23-2021 01:37
    I've used a couple different oddball clamps for this job.  Small nylon cable ties work well. Locate so hammers don't bind on each other. Tighten by pulling with needle nose pliers.  Have also used strong fishing braid-style thread to securely clamp with a knot. A burr oak acorn with its full helmet and a small stem helped hold the hammer being operated on out from its neighbors. Wish I had locatable photos, but alas.

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    Dwight D Denzer, RPT
    Dwight's Piano Works
    Springfield, IL
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  • 10.  RE: Regluing separated hammer felt

    Posted 08-23-2021 04:47
    I've done this a number of times, but never used a clamp. I remove the felt from the molding, apply accelerant to the felt, apply thick CA to the molding push felt onto molding and clamp with fingers for ten seconds or so and move on to the next one. I haven't done this in a few years, as I usually suggest to the piano owner that the repair is not so much a technical piano technician job as it is an arts & crafts type job and then ask if they would prefer to save a couple hundred dollars and do it themselves. They usually do. Result is usually not quite as neat as perhaps I would do it, but reasonably functional. I've not had a problem with any gaps - maybe there are some, but the felt ends up being glued on and the repaired hammer sounds equally bad as the hammers that had not come unglued.

    I experience no joy in saving a piano that belongs in the dump from the dump.

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    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
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  • 11.  RE: Regluing separated hammer felt

    Posted 08-23-2021 04:59
    Hi Tim,
    This is a very good question. I read the replies and I always learn something new. I just serviced a Winter spinet that has that problem. Because the client’s home is so far away from my home base, all repairs I do with it are on location, The piano is located in a beach house along the Chesapeake Bay where it is rather humid not unlike Hawaii.. I also try to figure out ways of doing repairs to spinets first without removing the drop action. At prior service call without removing the action, I used Locktiite gel CA between every other hammer and clamped them down with short thin cable ties around the felt as near the edges as possible without them slipping off. Although spacing between hammers are narrow, by pulling and locking the ties in with it's cinch on the top of the molding. Yesterday I returned for its semi-annual, clipped off the ties and prepared the neighboring group of delaminated hammer felts. This is done without removing the action. If I feel there is enough clearance between hammers, I will do them all in one service call without alternating. My client, a retired MD approved of my method agreeing with me that the cable tie method was like removing sutures after healing a wound.  I will continue to read all the cool posts coming in on this topic with excellent suggestions.

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    Kevin Magill
    Williamsburg VA
    757-220-2420
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  • 12.  RE: Regluing separated hammer felt

    Registered Piano Technician
    Posted 08-23-2021 09:54
    Try clamping with cable ties.  The ones that come with PLS systems work great.  They are even thin enough that the piano can be played if you leave them on until you return for a subsequent visit.

    David

    David Weiss
    Registered Piano Technician
    (434) 823-9733






  • 13.  RE: Regluing separated hammer felt

    Member
    Posted 08-23-2021 22:01
    I've been reading all of the interesting tips and tricks people have for regluing hammers.  I've tried several of those approaches, with varying degrees of success. 

    I will say that the very first thing I do is get some CA glue soaked into the end of the felt tail whether on top or bottom where they are still attached.  As I'm sure you know, once the felt pops off one side, the pressure is relieved and they usually stay attached on the other side.  If you try to close them up without preemptively gluing the other side, there's a good chance the other side will pop off.  So far my preferred method is to first spray CA glue kicker on the hammer felt (I hold a piece of thin cardboard over the wood so none of the accelerator gets to the wood), then I spread Zap-a-Gap CA glue on the wood.  Then I press them together, either by hand or with pliers or vise grips.  The real difficulty comes with the bigger bass hammers.  Getting those to close up well by hand is not really doable on those large hammers.  So then I have to use vise grips or pliers, which can be ok depending on the hammer shoulder width vs the size of pliers or vise grips.

    I have not had good success with zip ties on the bass hammers.  The zip ties seem to slip down the hammer curve too easily.

    Again, a big part of why I wanted to bring this question to the group was to find a way to do this job QUICKLY and efficiently.  Otherwise it's not worth taking on the job.  I have an action in my shop right now on which EVERY hammer felt needs to be glued down (except for maybe an octave and a half in the high treble).

    I like a lot of the ideas all of you have brought up.  But what about those big bass hammers.  They can put up quite a fight.  Anybody else have trouble with them?

    Thanks again for your input.

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    Tim Jasnau
    Makawao HI
    808-633-6655
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  • 14.  RE: Regluing separated hammer felt

    Posted 08-24-2021 01:17
    Hello Tim,
    Just like you do, I add a bead of the medium thick caglue to the side to which the felt is still attached.
    Pliers work well for me.
    For the bass hammers I just use big pliers, either a 12" or 16" tongue and groove.
    Peter

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    Petrus Janssen
    Peachtree City GA
    678-416-8055
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  • 15.  RE: Regluing separated hammer felt

    Registered Piano Technician
    Posted 08-24-2021 01:34
      |   view attached


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    John Rhodes
    Vancouver WA
    360-721-0728
    jrhodes@pacifier.com
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  • 16.  RE: Regluing separated hammer felt

    Registered Piano Technician
    Posted 08-24-2021 01:39

    This is a possible solution.  See two images (if Lower Logic managed to upload them). 
    I made an adjustable "bellyband" from two 8" zip ties, then secured the band and the hammer felt with a third 4" zip tie.  If you make the belly band fit the largest hammer, the band can be reused and adjusted for the smaller hammers after the CA+whiteglue has setup.

    I highly recommend the dark-red zip-tie cinching tool; it's made by Panduit and is available in the electrical tools section of hardware stores.



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    John Rhodes
    Vancouver WA
    360-721-0728
    jrhodes@pacifier.com
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  • 17.  RE: Regluing separated hammer felt

    Registered Piano Technician
    Posted 08-24-2021 03:24
    John, that's a really good method.

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    Steven Rosenthal
    Honolulu HI
    808-521-7129
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  • 18.  RE: Regluing separated hammer felt

    Registered Piano Technician
    Posted 08-24-2021 08:42
    Best I've seen yet. 👍

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 19.  RE: Regluing separated hammer felt

    Registered Piano Technician
    Posted 08-24-2021 09:26
    Hi All,

    I use the thread method. I stopped using glue only because I've never had them hold long term. I'm posting because I remember a TT&T in the journal that showed 2 hammers attached to some kind of clamp with the strike points pointing outward, not perpendicular. When clamped onto the offending hammer, the clamp hammers lined up opposite with the offending hammer & made a perfectly fitting clamp. I MIGHT have a picture of this I can share when I get home. If I find it, I'll share it. ;-) 

    Maggie

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    Maggie Jusiel, RPT
    Athens, WV
    (304)952-8615
    mags@timandmaggie.net
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  • 20.  RE: Regluing separated hammer felt

    Registered Piano Technician
    Posted 08-24-2021 13:44
    Hi There

    I have had success with pre drilling a hole thru the felt and thru the molding.
    I have used the extra screws from the damp-chaser unit install. 
    They are self taping, right length and do the trick in the tenor and bass sections even in the lower sections.

    Joe Morocco
    Needham MA

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    Joseph Morocco
    Needham MA
    781-449-9425
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  • 21.  RE: Regluing separated hammer felt

    Posted 08-24-2021 16:35

    Hi Joe, Nice repair, I guess you hold it/ clamp? while you pre  drill to align felt to molding, how about when it's peeling from the bottom end  tricky huh! 
    www.snowpianos.com



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    Martin Snow
    South Burlington VT
    617-543-1030
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