Thursday, 8 September 2011

Tools: Super Glue


Super glues or more correctly Cyanoacrylates are very useful for model making and I am sure many of you are already familiar with them.
However there are many pros and cons to using superglue and I am going to cover a few of those just now.
Cyanoacrylate is basically an acrylic resin that sets when it comes into contact with moisture. This is why it sticks skin together so well!
Firstly then, lets look at safety. Cyanoacrylate is extremely good at sticking skin and other human tissue together. I have glued my fingers together no end of times while holding a miniature that I am trying to assemble.

superglue

There are several way to release glued fingers, the simplest being acetone which is often found in nail varnish remover. A further caution here, acetone is also harmful to the skin, so use it sparingly. There are also various brands of superglue remover or debonder. All of these will likely be skin irritants.
If you do not have any of these things handy, I would suggest running the bonded digits under warm water for a while, as this may soften the joint.
Anyway lets move on to some of the uses for cyanoacrylate. Almost certainly most wargamers or figure collectors will have used superglue to assemble they figure with and it can be very useful for this.

Most cyanoacrylates set very quickly, usually in under a minute. Now if you are trying to hold two parts of a pewter figure together while they set, clearly a fast setting time is essential.

cyanoacrylate will often set almost instantly and this makes assembly of a figure so much easier. However sometime I have found that the glue will not go off however long I hold it. Clearly there is not enough moisture around to set the glue off.
Often simply breathing on the opposite surface to that which you have applied the glue, before bringing the two surfaces together can be enough to set the glue.
However if this is still not working there are several way around it. You can buy cyanoacrylate accelerators, which as the name suggests will speed up the setting of the glue. One well know brand that I have used is called Zip Kicker. It comes as a spray can and once you have put your two pieces together you spray zip kicker onto the surface and it sets instantly.

Superglue zap and zip

You can also spray the accelerator on to one surface and put the glue onto the other surface and then bring them together. This does not leave you with any time to reposition the two pieces though as they will, again, bond instantly.
There is a drawback to using accelerator though, as the bond will not be as strong as it would have been, if it had set naturally.
Alternative methods of setting off cyanoacrylate can include slightly wetting one surface with water before you bring the two parts together. This will only really work if the part you wet is porous, such as a piece of wood. I would not recommend it for sticking metal miniatures together.

Another technique that I have heard about, but I haven't tried yet is to apply a thin coat of PVA adhesive (commonly called “white glue”) to one surface and then superglue to the other. Now as I said I haven't tried it, but it would seem like a good idea, as the PVA contains water and should accelerate the setting of the bond.
OK, so you have your figures assembled and painted and you carefully pack them away in a case to take to a wargame. Then when you get there and open the box you find that several of the arms have snapped off, the glued joint has failed. Cyanoacrylate is great for sticking things together fast, but is is fairly brittle once set and does weaken after a few years.

I would always recommend pinning your joints rather than just relying on the glue. This involves drilling a small hole in to the two surfaces to be joined and putting a piece of wire into the hole, then gluing it together. This reinforces the joint and it will last much longer.
I would add that on bigger models and joints, I would recommend using a two part epoxy adhesive instead of cyanoacrylate. This usually means propping up the joint while it sets as the epoxy will take between five minutes and several hours to set, but the joint will be much stronger than if you used cyanoacrylate.

Finally, if you do want to take a "super glued" joint apart, try putting it in the freezer for sometime before dis-assembling the joint. Freezing the joint will make it more brittle and easier to take apart.

6 comments:

  1. Regular baking soda is a super glue accelerant too. If you have a small gap or hole that needs to be filled, pack it full of baking soda and then put a drop of superglue on it. It will set instantly and fill the void nicely. It is a very exothermic reaction. If you have baking soda on you hands and drip super glue on them it will burn.

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  2. War Frog,

    Thanks for that tip. I had heard about the Baking Soda thing but I'd never tried it.

    I will have to give it a go.

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  3. I tried out the PVA & super glue bond when I was building my Revenant Titan (along with mamoth size pins of course... I have to say, it worked a treat. I actually found that the mix I used allowed me a degree of flexibility before the connection set which gave me a little bit of wriggle room to get the exact pose right.

    Also, interesting fact: superglue was originally developed for the treatment of battlefield wounds (Vietnam). It can stop bleeding instantly and help seal up wounds until the patient / victim could reach a hospital. It really is no wonder it sticks fingers together so well... that's the point!

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  4. oink:

    Actually the Vietnam battle field story is a myth. It was originally developed in the 1940s while some scientists were trying to develop a new material to make gun sights. The stuff was too sticky and was abandoned. The Kodak took it on and developed the glue.

    It has been used for wound dressing since, but that wasn't it's original purpose...

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  5. Interesting stuff! I like the sneaky suggestion with the PVA, will have to try that at some point. I don't always get on with accelerators - my clumsy hands sometimes need a couple of goes to line parts up properly - but something to encourage the glue along is always welcome.

    Also, pinning grrraaaarrrgh no. Too fiddly for me. I've ruined far too many spindly little areas with clumsy drilling. Will take having to reglue models as the price for not having to disguise metalwork too fiddly for the aforementioned cludgy meat-fists.

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  6. Thanks for sharing a lot of valuable information about glue, David. I also had my fingers stuck together while I was trying to fix a small figurine. Instead of pulling my fingers apart, I soaked them in warm water for a few minutes, which solved the problem. Anyway, using white glue to accelerate the setting of the bond seems promising. I'll make sure to get on it soon.

    Shannon Mcniel @ Instant CA

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