Long-Term Performance of Cyanoacrylate Adhesive Bonds
A little informed speculation on the longevity of CA glue bonds. September 29, 2010
Question
On another forum, I mentioned that I would soon be building a project which has 88 small drawers, and that I was thinking of trying CA. Another woodworker responded with "I've heard CA deteriorates in about ten years and joints made with it can come apart."
I guess I missed reading this on the label. I am finding plenty of information about shore shelf life, but was not aware of a longevity problem with the final application. Is there any technical information that anyone of you may be aware of?
I am sure there may be some products out there that will self destruct regardless of the glue choice, which the maker would like to blame on the glue. Are there problems with this or any other adhesive which lose their strength in that short time?
Forum Responses
(Adhesive Forum)
From contributor J:
I'm no authority on the stuff, but my impression is that CA glues tend to be very hard and brittle when cured. I wonder whether they might be less tolerant of seasonal movement than softer, more elastic adhesives.
From the original questioner:
I am not an expert either, but I know that there are a lot of formulas which provide different properties for different end uses, and choosing wrong could tend to lead to failure as you point out due to seasonal changes. I can see how this would lead a lot of people to think that the glue had just quit working after that period. That doesn't mean that this was the case.
My reason for asking, is that I have a project coming up soon which has a bunch of tiny triangle shaped drawers, which will be a little awkward to clamp, but not so hard to just assemble and hold long enough for the speed of this type adhesive. I know I can just bind these parts together with packing wrap while using another glue. I like keeping this glue around and using it as another tool in my bag of tricks, but not if it has a working life that short.
From contributor K:
I've used the cyanoacrylate from Fastcap for a number of years. Granted on stain grade trim and molding, but it has never given me a problem or a call back. For what it is worth I have a friend who uses it on his model planes. I called him and asked about glue failure because he flies the planes regularly, and he says he hasn't had joints fail.
From Gene Wengert, forum technical advisor:
Many adhesives have a chemical reaction that occurs when it is applied and cured. Once cured, the adhesive is fixed for life (unless fire, etc.). A few water-based adhesives (such as old formula PVA) can return or move back toward their original condition with heat or moisture. Certainly many of the hot melts will become liquid and try to return to their original state with heat. The mastic adhesives (such as rubber glue and construction adhesives) will flow with time when they are under stress.
I am not aware of any adhesive that would last for ten years (give or take) and the fail. Joints will fail, but such failure is due to wood failure or excessive movement of the wood that then breaks the adhesive bond, and so on. Overall, it is surprising how well wood adhesives work, how easy they are to apply, and yet how inexpensive they are.
From the original questioner:
Thanks Gene. I know I had not read anything from a reputable source, but this was the second time I had heard that rumor in the last year. Also, I had several packages of hook and loop sanding disk which I was using out of, then suddenly all of them seemed to fall apart all at once. I don't know what kind of adhesive is used for that so I was a little apprehensive about using CA, even though it sure could speed up this little drawer run.
From contributor A:
We have used CA for years. SI (surface insensitive) or CA designed specifically for wood that usually is acidic will do the trick. We like FastCap 2p10 CA glue. It comes in Thin, Thick, and Gel viscosity and forms a strong bond even endgrain to endgrain. Also their activator does not turn the glue white. Moisture also forces the cure on CA glues.
From the original questioner:
Thanks everyone. A friend has offered to give me his PUR gun that he doesn't need or use. I think I should be able to get the speed and peace of mind with that.
