One little-discussed risk around CA glue is the fact that it will cause an exothermic reaction (heat/fire) when it comes into contact with natural materials like cotton, leather, wool, etc. — which includes things like your jeans, T-shirt, paper towels, etc.
The reaction can be fast, and depending on the amount, you could burn yourself or release a smoke that will irritate your lungs.
Please be very careful if you are working in a T-shirt or jeans — the safety data sheets for CA glues will tell you not to wear them while using CA.
I found this the hard way when applying CA with a paper towel, not thinking about what it was made from: I had put some accelerator on my pen body and started to apply the CA and my fingertips got suddenly very hot.
Luckily I did not get burned, and I solved my problem by slipping on a pair of gardening gloves which provided just enough insulation for my fingers given the small amounts of CA I was using — but it caught me by surprise, and I was glad it wasn’t worse.
None of the information here is certified or warrantied in any way. I am a hobbiest and sharing the best information I’ve learned, but I may be 100% wrong on everything and your safety is always your responsibility and you should verify and confirm information for yourself. Where possible I have included links to serve as a starting point for research for you.
The strength of CA glue is that it will bond to anything — which is also its challenge. But there is a short list of things it doesn’t stick to — and most of them aren’t easy to find for surface protection.
In general, particularly when you are using an activator, CA will be happy to find things to stick to.
Polyethylene
While this isn’t listed in the most popular article for “what does CA glue not stick to”, if you search on how to glue polyethylene, it’s often being discussed at the same time as polypropylene as something that is hard to glue.
My recommendation for performance, price, and availability would be to look for polyethylene gloves, either disposable or not depending on what you prefer.
I ended up getting these polyethylene gloves because they are thin, cheap, disposable, and it’s not an issue if some CA ends up adhering to them: Disposable Clear Plastic Gloves.
Alternatively, you can use something like painter’s tape (aka masking tape) to tape over your fingers to protect them (especially if you are using paper towels.)
If you are using paper towels, consider slightly thicker gloves (e.g. I have a set of polyethylene gardening gloves) if you are using my preferred method of applying the CA glue, because I found the heat uncomfortable on my finger otherwise.
The important part is having something to protect yourself and any surfaces that it may touch that you care about.
Are you aware that you could get burned if CA glue fell on your jeans and why paper towels could be a problem with CA glue? Read my article on CA Glue Safety: Natural Materials.
For the curious, here’s what I’ve learned about other plastics and additional research I did after reading the Starbond article.
None of the information here is certified or warrantied in any way. I am a hobbiest and sharing the best information I’ve learned, but I may be 100% wrong on everything and your safety is always your responsibility and you should verify and confirm information for yourself. Where possible I have included links to serve as a starting point for research for you.
Acetal Homopolymer/Copolymer (Delrin and Celcon)
I have been unable to tell if this includes both Delrin and Celcon, the two types of acetal plastics, or just Delrin. I suspect “both” since this article from 3M talks about how both are hard to glue, and this article talks about how they are very similar for most uses. The 3M article also notes how to use CA glues to bond them with the addition of a primer.
I haven’t actually tested this, because it’s not a coating used on gloves, but if you were looking for a surface to work with glue on, an acetal sheet may be a great choice (though if you use odorless you may run into problems.)
Polypropylene
I was unable to find any polypropylene coated gloves other than these, and they aren’t useful because they are a loose cotton weave and the glue would easily get on your fingers between the holes.
PTFE (e.g. Teflon)
The only gloves I was able to find that were PTFE-coated are expensive, bulky ones like these cryogenic gloves.
HDPE (High-Density Polyethylene)
HDPE has polyethylene at its base, but is a high density version, which I presume is why it’s more resistant to CA glue than regular polyethylene.
Plastic wrap is LDPE (low density polyethylene), making it an interesting option for protecting larger surface areas though I haven’t tried it yet.
CA glue can irritate your eyes, nose, mouth and lungs, because the fumes are a vaporized form of the CA itself and they react instantly with the moisture in your body just like they do with moisture on a surface or from a CA accelerant. About 1 in 20 people will also eventually become sensitized to CA fumes after repeated exposure and develop flu-like symptoms hours or days later. And finally, for some people, the fumes will trigger their asthma.
But lots of woodworkers work fairly freely with CA and just rely on their shop ventilation. You will need to evaluate yourself, your room setup, and your personal choices and risks to decide how much protection you want to follow and how much risk you’re comfortable with.
All manufacturers will provide the SDS (Safety Data Sheet — here’s an example from BSI) so you can read through and decide.
None of the information here is certified or warrantied in any way. I am a hobbiest and sharing the best information I’ve learned, but I may be 100% wrong on everything and your safety is always your responsibility and you should verify and confirm information for yourself. Where possible I have included links to serve as a starting point for research for you.
Work in a well-ventilated area (at a minimum a fan blowing fumes away from you) and if you’re using a mask, you’ll want a P100 respirator with organic vapor cartridges, not just a little N95 disposable mask.
Whatever mask you choose, know that they’re only as good as the fit and the seal. If air is getting in around the edges, that’s unfiltered air.,
A friend who is a woodworker says he often used an aquarium charcoal filter fastened to the back back of a fan sucking air away from his work area, but I don’t have any other information on how useful or effective that is.
Odorless CAand Fumes
Odorless CA smells less, and the companies advertise it as being less irritating than non-odorless CA.
However, if you read the SDS (Safety Data Sheet) for Supergold, it still notes “Exposure to vapors above the established exposure limit may result in respiratory irritation, which may lead to difficulty in breathing and tightness in the chest.” The established exposure limit is 0.2ppm averaged over 8 hours for all CA brands that I’ve been able to find, and they still recommend a NIOSH-approved respirator with a organic vapor cartridge (e.g. something like this.)
What this means in layman’s terms is: odorless CA is highly likely to be easier on your lungs. But it’s possible it may irritate your lungs anyways, so if you are concerned, you may want to follow the safety precautions for normal CA as well.
Personally I’ve chosen to use odorless CA glue (though it’s more challenging with bushings) with a respirator and fan, but I know many people feel they’re fine just with good ventilation and normal CA glue.
CA Accelerator and Fumes
I found it very challenging to find any safety information on CA accelerators online, so had to go to the manufacturers directly and read the data sheets.
(Updating this section now)
Follow the same safety precautions you do with CA glue and be aware that, like non-odorless CA glue, you may develop an allergy with repeated exposure if you aren’t careful.
Pen makers can use “CA” glue to finish their pen barrels, and works regardless of whether your pen barrels are wood, acrylic, or polymer clay. It even works fine with many standard polymer clay surface treatments.
CA glue is sometimes called Superglue or Crazyglue, but those are both specific brand names. “CA” comes from “Cyanoacrylate” (Wikipedia) — and no, there is no cyanide in it despite the “cyan” in the name. It’s an acrylic resin.
They form their bond when exposed to moisture, which means they bond very well and quickly to human skin, and also means that their bonding time is faster in humid air and slower in dry air. So if you live in a climate that swings between very dry and very wet, you will need to adjust your technique, and if you live in an exceptionally dry or humid area, be aware that you may end up with more or less time to work than what you see in videos.
Take proper cautions around fumes, avoid having your skin glued together, and be careful of exothermic reactions, but remember that CA glues are agreed upon to generally be safe by the UK and US.
The next few posts after this one go into more detail on CA glue safety.
Shelf life
CA glue does not have a long shelf life. Opened it lasts for about a month (though Mercury says their bottles have caps that let them last longer) and unopened only about a year. Most people will want to buy the smallest bottle they can, as you don’t use very much on each pen.
If you do end up buying in bulk, you can put it in the refrigerator to increase the shelf life from 12 to ~15 months, but make sure it warms up throughly before you open it: condensation inside the bottle would start the bond and could ruin the bottle.
Brands of CA
Not all CA is created equally for pens. If you have had issues in the past with cracking or cloudy CA, it may have been how you were applying it but may also have been the brand.
Per the excellent information on Toni’s site, one of the key things to look for is a CA glue with “flex”, to reduce the chance that you will get cracks or spidering during stress. One example is PMMA (poly methyl methacrylate).
I chose to buy Bob Smith Industries CA glue due to the recommendation on Toni’s site: “Other brands such as super-gold by BSI use other ingredients which works even better.” I got the Supergold thin and Supergold+ Medium because I wanted odorless CA (see below.)
I’ve also heard good things about Mercury from some other polymer clay pen makers.
Odorless CA costs about twice as much, but (quoting from the Bob Smith Industries page on Supergold) “eliminates the irritating fumes from the evaporating monomer that make repeated use of CA unpleasant at times.” (But: see my article on CA Glue Safety: Fumes before assuming that Odorless CA or accelerator are perfectly safe.)
CA Accelerator
Because you’re just spreading CA on a surface, rather than pressing two pieces together, and then putting on multiple coats, you may find CA Accelerator useful. However, as I learned on Toni’s site, the ingredients in accelerators can cause some of the cracking/clouding problems.
Specifically, the page says, you want to avoid accelerators with acetone in them, and look for ones like Naptha and Heptane. If you aren’t sure, you need to find the manufacturer’s website, they will have the MSDS/SDS (Material Safety Data Sheets) there and you can read what’s in them. For example, here is the relevant part of the BSI accelerator’s SDS:
She recommends the following brands, but I suggest you click through to the page to see if there have been any new ones added, and to see the ones she is recommending against as well.
My preference is ones like the BSI InstaSet, because they aren’t an aerosol, but are a pump action. I explain why in my article on applying CA to the pen body.
Applying CA glue
While I have a longer article on this as well, the short and sweet is:
Your surface must be completely dry (so don’t pre-treat with something like modpodge)
You should have already sanded your blank to at least 800 grit, as any big scratches will be amplified by the glossy surface (just like what happens when you try to use resin on a scratched piece)
Getting CA off your bushings is a pain; if you have regular CA you can use plastic bushings that don’t bond to CA, but if you’re using odorless you will need to use paste wax on the bushings
For more information, see my article on applying CA to the pen body.
Safety: Fumes
If you are new to CA, I’d recommend reading my post on CA Glue Safety: Fumes for more detail on handling CA glue (including odorless) and accelerator safely.
If you didn’t know you can get a chemical burn from CA glue and your jeans, you may want to read my article on CA Glue Safety: Natural Materials
I am very grateful toTony Ransfield Street (Etsy) and Ed Street for posting a primer on using CA Glue when making polymer clay pens. While I’ve expanded on it here with what I’ve learned, theirs was the first really good information I was able to find and I appreciate their generosity.
None of the information here is certified or warrantied in any way. I am a hobbiest and sharing the best information I’ve learned, but I may be 100% wrong on everything and your safety is always your responsibility and you should verify and confirm information for yourself. Where possible I have included links to serve as a starting point for research for you.
