Thread: Help With Cyano-Acrylates

I may be repeating some info here but I haven't seen this anywhere on these forums. For everyone who is having bad experiences with cyano-acrylates, here are a few tips:

• Don't touch wet CA!
• Use a little dish or the bottom 1/2" cut off a paper cup. Put a healthy puddle of medium weight CA into the dish and use a cheap brush or a pad made from paper towel to apply the CA to your project. Don't fiddle with it. Just paint on as even a layer as you can then hit it with a quick, even shot of aerosol accelerator from at least ten inches away.
• Clean the cured surface with isopropyl alcohol before your next coat. This will remove dust and any remnants of accelerator.
• It is infinitely better to apply many thin coats than one or two heavy coats. You will be sanding and polishing to even the surface so don't try to puddle the stuff to even it out.
• Don't breathe the fumes!!! The first word in the chemical name is CYANO! That's very similar to cyanide isn't it? Well cyanide is the gas used in gas chambers to execute people. For the same reason don't try to glue cuts closed. There are instant adhesives used in medical applications but that's not the same stuff you are getting at the hobby shop.
• Have fun! Practice on some scrap wood until you gain some proficiency. Remember, the glue is cheap and most wood grows on trees. Practice!

I hope these tips are helpful. I invite everyone who has some CA wisdom to add it to thread and we can build a growing repository.

Brad

I wanted to add one tip to what Icedog has already provided. When you go to sand out the uneven spots between applications do it under a slow stream of water. I have found that 400grit wet dry paper will produce less of the ugly cloudy white spots if you sand with running water. I am not really sure why. It may have something to do with the heat, or the sanding dust sticking back to the CA finish. I do know that since I started wet sanding with running water my CA finish is looking much much better.


I still use laytex fingers cut off the glove to apply it instead of a brush, but Icedog's method makes sense. I guess I have been lucky. So far have not had any problems that I was not able to correct with a little trial and error.

Just a couple of clarifications, I'll point them out here with a link for further reading.

CA's are not anaerobic as anyone who uses them for finishing can attest to. They will cure left on most any surface in the presence of air. To quote from the reference link below: "The vinyl structure of 2-cyanoacrylates makes them prone to spontaneous polymerisation. The chain propagation can be initiated by ionic, or radical mechanisms. The rate of polymerisation depends on temperature, humidity, light and the presence of accelerators like peroxides, or bases."

The reason skin bonds so quickly is because of the moisture in the skin, it acts as an accelerator. You can hasten a bond of thin cyanoacrylate by breathing on it.... My thin CA frosts over instantly when I do this.

There are anaerobic adhesives which are commonly sold as thread locking compounds.

As for using paper towels to distribute CA, sometimes the PH or moisture content in the cellulose can accelerate the polymerisation, several woodturners who use CA for finishing small items have noted that polyester batting seems to be more benign and tends not to accelerate the hardening. Such batting can be purchased from any Fabric outlet as it is used for padding and such in garments.

Sanding CA finishes: Cured CA = Acrylic Plastic = Thermoplastics. In other words, rub that finish so hard that it heats up and it can melt and gum things up. Not normally a problem if hand sanding but when spinning a finished item on a lathe it's a different matter. Even if using an accelerator, it can take quite some time for a thicker layer of CA to fully cure as it is only the surface that reacts with the initial shot of accelerator. Curing can take up to 24 hours if the layer is very thick and the humidity is very low in your work shop... pockets of not quite cured CA is the most likely source of those white spots that develop when you start sanding.


Regarding safety I'll offer this quote from the link below: "CA adhesives produce sharply irritating odours to the eyes and mucous membranes. CA’s should only be used in areas that offer excellent cross ventilation. If your studio does not offer good cross ventilation with fresh air, you should wear a good quality respirator with the appropriate vapour cartridge installed. Sensitive individuals should only use low odour, or low bloom products." The low odour CA's are also sold as foam compatible adhesives in Hobby shops where they use them for gluing Styrofoam parts. Here's a quote from Mercury Adhesives regarding their foam compatible glue:

"M100F foam compatible adhesive

AVAILABLE SIZES: 10GRAM, 1oz

DESCRIPTION: M100F is a Foam Compatible, low odor and lower to medium viscosity cyanoacrylate that provides a "low bloom" cure on plastics and other materials.

APPLICATIONS: Normally used where cosmetic requirements dictate an invisible bond without the problem of whitening or blooming. Can also be used on various foams and costume jewelry fabrication where fine, close up work dictates the use of a low odor, more user friendly product.

USEFUL HINTS/NOTES: Bonding can be immediate so careful, speedy alignment of parts can be required."

Rather than type more, please visit the following websites for more in depth information:

Cyanacrylates at woodturningvideosplus.com

Mercuryadhesives


Regards

Christian

this may be a dumb question, but here goes. Is CA the same as the active compound in Super Glue?

Originally Posted by beardnomore

this may be a dumb question, but here goes. Is CA the same as the active compound in Super Glue?

Yes. Super Glue, Crazy Glue, Zap and many others are all cyano-acrylates.

Originally Posted by icedog

Don't breathe the fumes!!! The first word in the chemical name is CYANO! That's very similar to cyanide isn't it? Well cyanide is the gas used in gas chambers to execute people. For the same reason don't try to glue cuts closed. There are instant adhesives used in medical applications but that's not the same stuff you are getting at the hobby shop.

Actually, while the medical adhesives are chemically different it's not because of the Cyano group, they both contain it. That would be the same line of logic as saying "Sodium Chloride, hmm chloride is very similar to chlorine! Isn't that the gas used in WWI by the Germans to kill people. Guys be careful when eating table salt." While I'm not advocating breathing the fumes I am pointing out a flaw in your logic that may lead to unnecessary worries by people who have used it to close wounds. Studies have actually shown that the use of the ethyl CA's, which includes super glue, crazy glue, etc., is safe. 2-Octyl CA's are just better suited to medical uses since they degrade more slowly.

I believe the *other* reason for the different formulas for medical CA's is the cure rate... the stuff we use generates significant heat during the polymerization process. Here's another quote from the link to the woodturning site: "Medical grade cyanoacrylates by contrast, are typically n-butyl-ester, isobutyl ester, or octyl ester based and are specially prepared to cure with as little heat during polymerisation as possible. Excessive heat or rapid cure during polymerisation can lead to tissue necrosis."

Regards

Kaptain "I dislike necrosis, particularly when my internal organs are involved" Zero

I use super glue whenever I have a bad cut. not on my face, never had a bad cut while shaving, I usually get cut working with barbed wire fences. Works fast and better than a trip to the hospital for stitches. I have never had problems develop while using this on wounds. then again this might just be me, YMMV

A wee problem cyano also means blue i.e. cyan which is this color http://www.foxpup.com/printertest/Cyan.gif

Sorry, I am sure that this is a dumb question. Someone said that many superglues are CA glue, but are all superglues CA? I went to a big box home improvement store looking for something listed as CA but found nothing. Also someone said that medium weight CA should be used, would that be listed on the packaging anywhere? I don't really want to pay shipping for something that is available locally, so I am hoping a regular superglue would work. Any advice is greatly appreciated!