[pianotech] CA Glue

Susan Kline skline at peak.org
Thu Sep 9 18:05:02 MDT 2010


  Hi, Terry

I find it difficult to imagine how you got a mixture of white glue and 
CA glue NOT to set up!

As for the accelerator -- sure, it sets up CA extremely fast, but it 
also stinks. I don't know what is in it, but possibly it uses solvents, 
or something which is toxic, since the one time I used it it was so 
irritating. White glue is very non-toxic and so easily available.

Also, I imagine that the white-glue-CA bond is tougher than the 
accelerated bond, possibly just because it takes a few seconds to set. I 
think that an absolutely instant bond isn't as robust long-term, though 
this might just be my idea. Possibly people should do comparative tests. 
I don't feel like it, because I don't want to breathe any of the 
accelerator.

Once the joint has set up, it can be pulled apart fairly easily for a 
few minutes. It gets firmer and more determined within the hour, though. 
At least it has seemed this way to me. I like this feature, because if I 
do something wrong, I can take it apart if I catch it quickly, and then 
do it over again, after refreshing the glues.

As for the bond of CA-white glue being stronger than CA alone, it was 
just my own experience. If I use CA glue alone, and get a little on my 
fingers, and they stick to something or each other, I can pull them 
apart, and just lose a thin superficial layer of skin. But the time I 
managed to have a little white glue on my index finger, and got some CA 
on my thumb, and THEY stuck together .... ! ! ..... the bond went deep 
enough I could tell that they were not coming apart, and if they did, 
I'd have a bleeding wound to deal with. I had nail polish remover in the 
car, and I had to walk out there with my thumb connected to the middle 
of my index finger, and it took a lot of work and repeated dousing with 
acetone to get them apart. I only did that once (smearing white glue 
into a hole for a rubber button, then holding the button and putting the 
CA onto it, messily, and the thumb contacted the slightly white-glued 
index finger while pressing the button into the lid) but I never forgot 
the experience.

I don't think it's all that good an idea to repeat this experiment, just 
to validate the idea.

Trying to figure out why you didn't get CA and white glue to set up .... 
I wonder. I've tried the "trick" with many brands of water based glues, 
Elmer's, Titebond, yellow carpenter's glue .. all worked equally well. 
However, I have not used different brands of CA. I've used Loctite 
brand, water thin, throughout. It has always worked, unless it got so 
old that it thickened in the original container.

One could also consider quantities of each, but I've found the "trick" 
to be very tolerant of that. A pretty good ribbon of white glue with 
just a few minor dots of CA dropped into it set up pretty well. Small 
scanty smears of white glue with a layer of CA on the other piece 
(assuming it was non-absorptive, wood or cardboard instead of cloth) 
worked just fine. Someone used the "trick" to glue a thin wood carving 
onto a piano leg, using LOTS of both, and it squeezed out into a sort of 
foamy ooze, but the bond set up, and he was able to pull off the extra 
all in one string a few minutes later.

If the bond is working right, for instance, cloth to cloth or cloth to 
wood, within a few seconds of the two glues meeting you can feel heat 
through the cloth.

The CA mustn't be left just sitting around. I put the white glue on 
first, get it where I want it, then as soon as the CA touches it, the 
parts or cloth must be pressed together immediately. Once the CA is wet 
(in contact with water), it crosslinks and turns solid very quickly, and 
once it is solid it won't glue anything it wasn't already touching while 
liquid.

Possibly if you gave me more details, Terry, I could figure out what 
might have happened.

The original article is in the October, 1997 Journal.

Susan Kline

On 9/9/2010 5:41 AM, Terry Farrell wrote:
> I've tried the white glue/super glue thing and it never seemed to set 
> up. It's definitely NOT instant. Maybe I just didn't want to wait long 
> enough - but then, that is one of the major advantages of super glue - 
> bonds can be within seconds - and is often one of the criteria I use 
> in selecting CA for a particular application.
>
> What is the basis for your claim that the CA/water-based glue joint is 
> much stronger than CA alone? With "CA alone you can truly glue 
> yourself to yourself in a way which requires acetone and a lot of 
> patience and determination to reverse. Don't ask me how I know...."
>
> I hope I don't sound too much like I am berating your Susan! I don't 
> mean to do that at all. My interest is that I don't want to be missing 
> out on any great little tech tip like this seems to be....... but I 
> just haven't been able to figure out what is the advantage of this 
> over CA with accelerator.
>
> Do you have a reference for your Journal article? I do remember 
> reading it, but it's been a while.
>
> Thanks!!!  :-)
>
> Terry Farrell




More information about the pianotech mailing list

This PTG archive page provided courtesy of Moy Piano Service, LLC