Jumping on to second Blaine. I've also run across way too many pianos with key tops that have been super glued on and have popped off again. I also started using the Gorilla brand of super glue (blue lid, not green lid which is gel type) for keytops. No accelerant. I apply a thin spiral on the bottom of the ivory, rub it over the surface of the keytop a couple times to spread the glue, and then clamp it for a few minutes. the gorilla brand allegedly has some kind of plasticizer in it that makes the cured glue less brittle than off the shelf ca glue.
Glue aside, I would say that the most important thing I've learned in reattaching ivories that the customer saved is to attach each ivory wafer to the key it came from originally. It's easier than it sounds.
First, sort the ivory pieces by note by looking at the top edge. Look for the rounded "notch" side where each key meets the bottom of a sharp and the cleaner flatter surface where it butts up flush against the tail. Sort them into 3 groups: Cs and Fs, Es and Bs, and all the rest that have sharps on both sides (D, G, A). You can then sort this third group down to individual notes by looking at the relative lengths of the notches. D has equal lengths of sharps on both sides. G has a little longer sharp on one side vs the other, and A is the mirror of G.
You now have up to 5 groups.
Next, take each group, and go through the keys belonging to that group (eg. Cs and Es) and match each ivory to the key it came off of. Look at where it mates with the tail and make sure that lines up exactly. There will be small differences that you can see. Same goes with the key width. Finally, turn the ivory over and look at any imperfections in the way it tore off the original wafer. Sometimes bits of the original glue wafer stuck to the Ivory while most of the wafer stuck to the key. You can see when these match. When you find the right match, the ivory will almost snap into place, and you won't be able to slide it side-to-side easily. It will just fit. That makes gluing so much easier that it's definitely worth the trouble, and the piano will look better when you're through.
The exception is when you're regluing Ivory that has already been reglued in the past and has popped off again. In that case using the roughness on the bottom to mate isn't going to work. In that case, I file the bottom of each ivory and the top of each key somewhat to get a smooth gluing surface and mate the tops as best I can, because the previous person most likely didn't go to the trouble of matching the ivory to the original keys.
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Anthony Willey, RPT
http://willeypianotuning.comhttp://pianometer.com------------------------------
Original Message:
Sent: 11-05-2024 01:19
From: Blaine Hebert
Subject: Regluing ivories
Last Thursday I worked on an ancient grand that had about 7 missing ivories. I was able to find most of them between the keys or inside the action. Every one of the ivories were previously repaired with CA glue. It took me an hour to carve and scrape off the CA glue to get down to a smooth and level surface that I could re-glue. I personally use contact cement in the field. I have found that contact cement has a 20 year life-span under a key, but that will outlive the life of this particular piano as well as most older uprights, which is the usual situation on key repairs.
If I was actually going to use a CA type glue I would use Gorilla clear glue (the non-expanding type). This requires lightly spraying one surface with water and the glue requires 30 seconds to a minute to cure. Gorilla glue has one of the best adhesions that I have tested.
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Blaine Hebert RPT
Duarte CA
(626) 390-0512
Original Message:
Sent: 11-04-2024 20:32
From: Geoff Sykes
Subject: Regluing ivories
OK, I know I should already know this but I experience it so infrequently that I forget. What's the recommended glue to use when regluing old ivories that have popped off? The customer has saved all of them. Just needs them reattached. Not that it would change anything but it's an old Baldwin grand.
Thanks --
-- Geoff
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Geoff Sykes, RPT
Los Angeles CA
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