CAUT

  • 1.  reattaching ivory

    Registered Piano Technician
    Posted 09-27-2023 10:47

    Greetings,

    It has been decades since I last reattached a loose ivory keytop. When I last did it, it was with one of those cloth wafers impregnated with adhesive that is activated when wetted, the keytop clamped in place with a heated brass plate.

    Wondering if there are any newer, slicker twenty-first century ways of accomplishing this task.

    Thanks,

    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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  • 2.  RE: reattaching ivory

    Registered Piano Technician
    Posted 09-27-2023 17:57

    The last few replacements I did was with white PVC-E glue, clamped in place. Each turned out well and I've not seen any issues so far. 



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


  • 3.  RE: reattaching ivory

    Registered Piano Technician
    Posted 09-27-2023 19:33
    I'll mention that if a glue containing water is used, clamping until cured is an absolute must. The ivory will curve/warp otherwise. 

    I think Susan Kline swears by CA on the ivory, something like white glue on the ivory, the white glue serving to accelerate the set of the CA.

    I've used CA successfully several times. I used to use Duco cement successfully many years ago. It seems to be available still (haven't seen it in my local hardware for years, so thought it had disappeared). With Duco, no clamping was necessary. 
    Regards,
    Fred Sturm
    http://fredsturm.net
    www.artoftuning.com
    "Art is not a mirror held up to reality, but a hammer with which to shape it." Brecht




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  • 4.  RE: reattaching ivory

    Registered Piano Technician
    Posted 09-27-2023 20:41

    Benjamin,

    Thanks for sharing your experience with PVC-E glue.

    Wim,

    Someone else suggested CA glue (privately) as well. Sounds like it, too, can work.

    I was planning on removing the key from the action to perform this task.

    Larry,

    Trophy tape is something I had not yet heard of for this application. Using it in this particular situation might be facilitated by the fact that it is one piece ivory.

    Fred,

    Thanks for reminding me about Susan Klein's method. Do you recall which substance she puts on the key and which on the ivory? 

    Daniel,

    Thanks for your generous offer to send me your wafers, but I'm trying to quit!

    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


  • 5.  RE: reattaching ivory

    Registered Piano Technician
    Posted 09-28-2023 05:57
    Greetings,
       I would be cautious if I had to use Susan's method on a one piece ivory, as it bonds quite quickly and permanently.  My preferred approach is to clean both key and ivory with a wipe or two of acetone, then clamp   the ivory down on a thin film of thin hot hide glue.  I rarely have to add whiting but will if the key surface is darkened.  Nice,traditional, repair, but it takes time and is hard to do in the field without two trips and a piano out of commission.  

         PVC-E worked well while it was available.  I have used CA gel, but would also clamp that for 5 minutes or so. I have also used thin CA, (and glued myself to a key...) in an emergency.  
    Regards 



    Original Message


  • 6.  RE: reattaching ivory

    Registered Piano Technician
    Posted 09-29-2023 11:15

    If I use CA glue on a key top, I tape up my fingers with masking tape to avoid gluing myself to the key.  



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    Robert Callaghan RPT
    Reno NV
    (775) 287-2140
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    Original Message


  • 7.  RE: reattaching ivory

    Registered Piano Technician
    Posted 09-29-2023 15:17
    When I have used CA, I tape the ivory head with a 'hinge' of tape to the tail.  First I put it in posiiton, and  while pressing the head back into the tail, I put a piece of blue tape on them.  After spreading thin or medium CA on the underside of the key, I just rotate it into position and let the tape control the alignment. Hold it down for 30 seconds and it seems to be a durable repair, (though I would prefer the time, space and payment it takes to restore these bonds with a thin wipe of hide glue and clamps...)

            If there is room and time, I do use a spring loaded key top  clamp with a head plate and leave it for a few minutes. Might not make a difference but it seems like cheap insurance. 

    Regards, 



    Original Message


  • 8.  RE: reattaching ivory

    Registered Piano Technician
    Posted 09-28-2023 09:36
    I don't remember specifically what Susan wrote, but I wrote CA on the ivory, white glue on the wood. That way the moisture has wood to go into, and maybe the CA seals the ivory from the moisture a bit, avoiding curling.

    Regards,
    Fred Sturm
    http://fredsturm.net
    www.artoftuning.com
    "Art is not a mirror held up to reality, but a hammer with which to shape it." Brecht




    Original Message


  • 9.  RE: reattaching ivory

    Registered Piano Technician
    Posted 09-29-2023 02:07

    I have tested Titebond Melamine glue and it is essentially the same thing as our old PVE glue.  It works about as well and acts the same, I suspect it is simply a version of PVE.

    I also tested Gorilla Glue Clear.  This requires dampening the wood before applying the part with a coating of glue.  In my test it bonded as well as or better than anything else.  This product doesn't foam or expand.

    If you promise not to tell anyone I will admit to frequently using Weldwood Contact Cement for keytops, especially on old uprights and ivory.  In my experience Contact Cement has a 20 year lifespan, after which it dries, becomes brittle and will detach, though after 20 years you can claim to not know anything about who used it way back then.  It also tends to darken key tops a bit and will show through more than PVE glue.

    Personally, after scraping off CA glue from dozens and dozens of badly applied key tops I never use the stuff for keytops.  It has its place, but its not for me. 

    Properly applied hide glue might just be one of the best adhesives out there.  Those glue wafers held and are still holding key tops on for over 100 years.  400 year old violins are still being held together with their original hide glue. Egyptian tombs 4000 years old have objects held together with hide glue.  



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    Blaine Hebert RPT
    Duarte CA
    (626) 390-0512
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    Original Message