In a message dated 5/17/00 8:16:54 AM Central Daylight Time, draine@mediaone.net (J Patrick Draine) writes: Clyde Hollinger wrote: writes: << I used to use CA to glue on the miscellaneous ivory keytop, because it was quick. > I stopped using it when I found some of the ivory heads popping off again in a > year or two, which caused me to think the bond was too weak. Maybe it was the way > I did it; I put the glue on the key and accelerator on the keytop, then held them > in position for ten seconds or so, and that was it. (snip) Perhaps "a thin coat" is "the ticket." I don't use contact cement, because I've often seen it leach into the ivory, leaving it an ugly, mottled gray (smells bad too). (snip)>> I've had the same experience with both of these. I believe the accelerator is the culprit with the CA glue. You need it if you want a fast cure but it causes the glue to "fry" and makes a weak bond. Contact cement or "Goo" glue from Schaff Piano Supply (or a hobby or hardware store) worked fairly well but they both discolor and sometimes also fail after a year or two. Although I haven't been able to time test it yet, I have a lot of confidence in the CA-white glue combination. I have used it in a number of other applications and am really happy with it. With both surfaces scraped clean and the ivory cleaned with an abrasive if it has overly yellowed, spread CA glue sparingly but evenly on the ivory while avoiding the edges (so you won't get excessive squeeze). Spread the white glue in the same manner on the key. Place the ivory piece carefully, press firmly with the thumb and fingers and hold for about 30 seconds. A set will take quickly and a solid cure within hours. After another few minutes, wipe any squeeze away. The white glue serves as a catalyst that causes the CA glue to set in less than a minute and firmly within a few minutes or so. The wet white glue cures after a few more hours. The initial set is strong enough to handle after a minute or two. The problem with the usual accelerator is that it works too fast, making a week bond. The slower set from the white glue appears to be much stronger and more solid. This all, of course, is for quick repair on old, worn and weathered uprights (maybe crummy old grands too), not really fine pianos. For the finer instruments, the traditional methods are what is appropriate. This kind of repair, which is often called for, is the kind that falls in the "Hospital for Hopeless Pianos" category. One good advantage is that it does not discolor and also does not leech like contact cement. I have a question about ivory wafers that I could not answer when someone asked me off List. I will post it later. Regards, Bill Bremmer RPT Madison, Wisconsin
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