Official Luthiers Forum!

Hey guys,

I guess most of you who use superglue know that when you wipe of an excess with a paper towel it will sometimes get really hot. On a few occasions I've noticed that along with fumes that nearly knock me onto the floor, something that appears to be smoke is coming off the paper towel.

I can't decide if this is smoke of just chemical fumes. It certainly looks like smoke, and it's certainly hot. Do any of you chemical guys know definitively if it is smoke? Is it prone to spontaneous combustion? More at the point, could it catch fire if thrown into the trashcan before it stops reacting?

It won't combust itself, but throwing anything hot in to a trash can is
certainly a dumb thing to do. Uncured CA and any rags wet with a solvent
should not be thrown directly in to a trash can. If you have a rag wet with
with naptha, acetone, thinner, uncured epoxy, it should always be left out
to dry or harden before being disposed of.

I don't know what the chemical content of the CA vapors are, but they're
nasty and ventilation is a must. At the very least a fan blowing fresh air
across can be helpful. About ten years ago I called the folks at Aron Alpha
to ask them about this, and never got much of an answer. They told me it
was relatively harmless, and simply somewhat annoying to the eyes and
sinuses, somewhat akin to cutting an onion. I don't believe them for a
second, and try to be reasonably safe with a small bench fan for
ventilation. I never got a name of the resulting chemicals in the vapors
produced during curing, but it sure doesn't smell or feel good.

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Eschew obfuscation, espouse elucidation.

The Super Glue Gel MSDS sheet includes this:



"Contact with cotton or wool may result in a strong exothermic reaction which can result in a fire."



I've never seen smoke from super glue, but it sounds like you ought to assume it is.  Fire in the shop is generally bad.

I'm not a chemist, but I remember reading once about the super glue type stuff doctors use instead of stitches.  They originally tried regular super glue, but the bonding reaction put off too much heat and would cause some burning of the tissue, interfering with healing.  It took some scientist types to develop a similar chemical that bonded much more coolly.  I don't know if these cooler glues are available to the public, but maybe different brands or formulations have different heat outputs?

Miek

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Mike Lindstrom

It's smoke and this can be demonstrated by dropping some fresh "thin" CA on a very soft wood joint like balsa.  If the CA is fresh and a quality thin CA it will smoke on balsa every time.  Hence brand names like Hot Stuff.......  It only happens for a second and is just a puff of smoke.  As David said ventilation is very important and if you visit some radio control model airplane builder forums you will find discussions about the "CA blues" caused by using CA in poorly ventilated areas.  Some people actually get sick, feel depressed, and generally down when exposed to excessive CA fumes.

Another good practice that I do is to never throw any combustibles in the trash.  I use paper towels with say naphtha and when finished I tear up the wet paper towels and feed them in reasonable quantities right into the  toilet......  Something else that I try to do is to locate my trash can where the sun can never hit it and I also empty it often.

As CA was originally developed to seal cuts in lieu of stitches until a patient could be transported to a proper medical facility they quickly found that thin CA also burned the patient.  This led to the development of medium CA and later thick CA.

I was teaching RC flying at a very large, popular flying field and a newb sliced his hands, both of them, terribly in the prob of a rather large RC airplane with a small chain saw engine on it.  My partner and I (partner in the sense of we were both certified RC flying instructors...) had just been discussing using CA to seal cuts.  We looked at each other, out came the medium CA, and in seconds the bleeding was stopped before the ambulance arrived.  It was painless for the victim too.

Two weeks later we saw the same guy who nearly cut his fingers off and he had this terrible looking cut and more..... on his forehead.  When we asked him what happened he replied that he was under a car at work replacing a muffler and the thing let loose unexpectedly and cut the heck out of his head.  He went on to say that he used CA and it was not working to stop the bleeding and seal the cut so he sprayed his head with accelerator......  What resulted were terrible, scaring burns and a total lack of respect for this guy's intelligence  going forward.....  True story.

Paranoid?  Perhaps.  Alive to tell about it - yes

Modern CA glues do have some additives that make it not ideal to use on bare skin, even though that's what it was originally designed for. You can still get the original type sold as "liquid bandage" next to the regular bandaids. It actually works pretty well, especially for things like fingertips where a bandaid is awkward.

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Jonathan Kendall, Siloam Springs AR

In the Operating Room we have Dermabond. It is CA with an additive that
gives it some flexibility. Works great but expensive. I still end up using med
CA on my cuts at home. It just get hard and eventually cracks off

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Andy Z.
http://www.lazydogguitars.com

Dr. Andy, I'm glad to hear you say that! I used medium CA on a small shop cut in front of my wife and she went nuts...I told her of the military's use of CA for field wounds and all that, and she still thinks I'm nuts...ah, but now I have your post to print out and vindicate myself...SWWEEEET!

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http://www.presnallguitars.com

Oh, and if she questions your credibility I'll just show her your guitars!!!

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http://www.presnallguitars.com

neat thread

Hi Gerald~

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http://www.dickeyguitars.com

I seriously doubt it is smoke. CA is a moisture cure adhesive. I've used it for years in various products I've designed. Sometimes if the RH swings wildly, we have a huge problem getting it to cure, especially when RH drops below 30%. During Santa Ana conditions, we can have RH drop into the low teens and CA will not cure.
I suspect what we see is water vapor along with other products of the curing exothermic reaction.

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"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

What's the definition of "smoke"?

There are serious fumes that are emitted as CA glues cure. When it cures
fast you can see those fumes, and I don't think what you are seeing is
moisture. No, I don't think the white clouds rising from the curing glue
are the result of anything burning, but they certainly contain chemicals
other than H2O. I suppose that doesn't qualify it as "smoke" technically
though.


So I have to ask, am I the only one here who regularly makes mini CA
bombs by sucking some accelerator in to an old pipette with leftover CA
in it, and tossing it to a corner as quickly as possible? I though everyone
did this for fun.

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Eschew obfuscation, espouse elucidation.

Okay, found a decent answer. Pretty much what Aron Alpha told me years
ago that I didn't believe. Mercury adhesives has a good FAQ page.

"4. Why do CA fumes burn my nose / eyes and make my eyes water?

The fumes that you see coming from a glue joint is from the heat that is
generated during the anionic polymerization process, the fumes do carry
the cyanoacrylate within them, therefore when they come into contact
with mucus membranes (such as the nose, throat or eyes) the
cyanoacrylate reacts with the moisture contained within these areas and
cause a burning sensation. This process is not harmful to the body but
can be irritating; in some people it can be extremely irritating. This is not
an allergic reaction although some people are sensitized to this.

To prevent problems all you need to do is make sure you move air across
the work surface with a small fan. The CA vapors will dissipate very
quickly into the air and become saturated within the surrounding air. If
you are one of the few people that are very sensitive to the fumes you can
use the low odor M100F or M1000F CA, which will not fume and cause
problems."

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Eschew obfuscation, espouse elucidation.

This is a very informative thread from the James Randi forum.

http://forums.randi.org/showthread.php?t=48426/

A few posts into the thread, a chemist with LocTite chimes in with some inside information. 

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If you can't do something well, learn to enjoy doing it poorly.

CA gets seriously hot and smokes when dropped on to denim...trust me.

Hot crotch!

[QUOTE=JRHall] This is a very informative thread from the James Randi
forum. [/QUOTE]

I'm a bit skeptical of anything on that forum.

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Eschew obfuscation, espouse elucidation.

So here's a question for you guys....why can't we just superglue bracing onto the top? It sure would be quicker!

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http://www.PeakeGuitars.com

[QUOTE=David Collins] [QUOTE=JRHall] This is a very informative thread from the James Randi

forum. [/QUOTE]



I'm a bit skeptical of anything on that forum.[/QUOTE]

OK, that's funny

Guitar building was brought up late in the thread too.

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If you can't do something well, learn to enjoy doing it poorly.

CA makes a fairly brittle joint. Very strong in tension and shear but not so strong in torque. It could be done but think the failure rate with temperature changes would be greater at the braces than say binding because the brace joint is in motion when played. This repetitive stressing I think would lead to possible joint failure.

[QUOTE=Parser] So here's a question for you guys....why can't we just superglue bracing onto the top? It sure would be quicker![/QUOTE]

Nobody trusts the glue because it doesn't have 'a track record' is the answer I get. I know a guy who made an electric in the 80s entirely with CA and it's still fine, though.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

It does seem more brittle though..I could see where maybe it isn't the best stuff to use if the instrument is ever dropped or banged.(?)

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http://www.PeakeGuitars.com

I always used super glue as a repair glue, finish repair, inlay or other non critical use. In the past I have used it on other objects only to find them broken apart weeks later. Metal to stone. I have seen long lasting bonds with rubber but we use wood on guitars not rubber. They now sell a flexible CA but I would not trust any CA over a good yellow glue. Plus the cost difference would be Crazy (Crazy Glue ha ha). How would you clamp it or get enough on the top to bond it in time.

I think the smoke is two fold, one the reaction between the material and the glue and the heat generated by the cure. I don't remember smoke on the gel version because of it's longer cure time. Anything that cures that fast has to generate heat so I don't doubt it could combust on a material given the right situation.

As far as using standard CA for wounds I believe in an emergency yes but it stings if I remember right. Nexcare sells a small non sting tube for wounds called liquid bandage made for those long scrapes or floppy skin wounds. Bandaid also sells some in a Q-Tip type applicator but you have to add a hardener to the Q-Tip then apply. It is softer and more flexible than the Nexcare which is more like straight thin CA. But the Bandaid brand attracts dirt quickly. The only issue I have with the Nexcare is its very brittle and the tube or tip hardens before I can finish the whole 1ML .034 fl oz tube. I highly recommend the product though for people who don't like looking like a Bandaid ad.

[QUOTE=Parser] So here's a question for you guys....why can't we just superglue bracing onto the top? It sure would be quicker![/QUOTE]
The problem i see with super glue is they can absorb in to porus woods a little to fast and this can cause week glue bonds. And wood glued with super glue is not that hard to break apart cleanly at the joint unlike wood glues. Wood glues will usually break at the wood and not the glue seam.

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Guitars, guitars and more guitars.

CA when cured is not as hard as HHG or Fish glue.  Try chiseling off samples of either.  HHG is hard as a rock when cured.  This translates into the excellent acoustical properties that we want for musical instruments.  It's also repairable with some heat.

And like Bob mentioned you will not find any 100 year old instruments still in tact made from CA........

And.... HHG cleans up very easily, CA does not, and CA fumes are nasty.

Finally CA is way more expensive to use then HHG.

Superglue is toxic and hazardous to your health. Some friends use it (not
for guitar building - think CSI) and did not have a proper fuming chamber
with venting. Don't ask me what the effects of the CA are, but their lab was
shut down for some time for thousands of dollars worth of upgrades. They
did tell me that fresh air is a must.

Jamie