I know, this is probably a dumb question to most of you, but I have just returned to the hobby after about 27 years away from it, and I'm trying to get up on all the new techniques. I have heard about the use of "super glues", both as a bonding agent, and as a gap filler. This is something I'd like to try, but I'm having difficulty locating some tips on exactly how to use it. Is there a website I can go to that will give me some ideas on how to use super glue? Also, what are the best types of super glues to use. Is there one that'll do it all, gluing and gap filling?
Paul, I was thinking of super glues (cyanoacrylates or CAs) when I saw your post. Here it goes. There are as many brands out there as there are hobby shops. There is a particular brand "Insta-Cure and Un-Cure" that is sold under different hobby shop names. The bottles are a cloudy plastic and come in very colorful buffed aluminum over metallic blue, lavender, green and other colors. Then there is another popular brand, Zap-A-Gap, same thing, smaller bottles. Prices will set you back from $3.00 to about $6.00 for a .25 ounce to a 1 ounce bottle. If you are not going to use them for a spell, put them away in the freezer, that seems to extend the shelf life of the CA. Just make sure that they are labeled and no one thinks its something to add to the food. All CAs make things stick together - some fast, some slow and some really SLOW. The rate of speed for drying has to do with the composition of the CA, of which I know nothing about, except that they make things stick together, you see, I am an auditor and not a glue engineer. Some rates of drying are: 1 to 3 seconds,
5 to 15 seconds, 30 to 120 seconds. Then there are the accelerators, these cut down the drying or setting time in half or less. And of course you have the debonders, these unstick what you don't want stuck, like fingers to each other or plastic parts to fingers, or fingers to eye lashes (my brother-in-law). The slower the drying or stick time, the thicker the CA. For example, the 1 to 3 second time type is really watery, the 30 to 120 second type is more like a jelly, and it is perfect for filling gaps. Just be careful to just fill the gap because later on you will have to sand the excess and just might sand away half of your model, which will leave you with a really nice filled in gap. What to use CA on. It depends on what you are gluing together. When I work on my wood ships, I use the slow setting glue. For aircraft parts, I use the 1 to
3 second type and for plastic parts that don't require speed or waiting for Christmas, I use the in-between speeds. And then there are the myriad of projects around the house that may require a CA instead of Elmer's or a glue stick.
There, I hope this will give you an idea of CAs and how they work. If someone out there has a better mouse trap, bring it on and let us help the less fortunate.
Paul, Forgot to mention one thing about CAs, use very sparingly - a little goes a long way. Try not to apply directly from the bottle to the part/parts you are gluing. Make a small cup out of aluminum paper and squirt a bit in the cup, then apply with a tooth pick, or a straightened out paper clip, or a sewing needle that you snipped off half of the eye of the needle. Dip the whatever in the glue and then transfer (notice I said transfer) the glue to the parts. If the glue is new and the quick drying type, it should spread very quickly between the parts - that is called capillary action. Once this happens, press the parts together - quickly - until the glue sets, usually several seconds. This is usually when the fingers stick together or the the parts. If you do not have a debonder, plain acetone will do the trick of unsticking fingers or plastic from fingers. Or, denatured alcohol, but it is much slower to debond on skin.
I have learned some of the tricks of CAs on my own, and from members of the clubs I belong to here in Austin, TX. If you have the opportunity to join a local club, do so, the benefits are priceless and you get to meet new old farts and talk plastic.
Again, good luck and go build something.
Ray Aust> I know, this is probably a dumb question to most of you, but I have just
There are 3 main types of superglue( cyanoacrylates or CA) thin, medium, and thick. The medium and thick are concidered gapfilling and dry a bit slower than the thin but any of the 3 can be used succesfully in model building.
All the messages contain good info, but I never go without my trusty Super Glue Accelarator!
My modeling woudln't be the same if there was no accelerator! It hardens the CA glue in an instant!
I never spray it. I dab it on with a toothpick or with my latest find: a MicroBrush!
There are several brands of accelerator - all are compatible with all CA glues. But some use acetone as the carrier, so the can mar plastic. I use the "Bob Smith Industries" (BSI) brand. Safe on plastic.
I also use (BSI) low odor CA glue to glue in clear lenses - it doesn't fog them (sepecially when accelerated)! :-)
There's a lot of weird stuff being sold nowadays. I bought a 3-pack of glue from an ebay seller and the medium vicosity is intolerable. The thin and the thick *act* like super glue but the medium is almost like an unrelated product. Doesn't set well or fast and seems excessively soft after curing, leaves a lot of soft white 'angel hair' around a joint where it might tend to spread out.
I've bought good bargains on glue in the past but based on this recent experience I think I'd rather stick with (pun-hehe) the name brand stuff. Saving a buck or two doesn't make sense if it screws up your projects.
Baking soda also works as an accelerator. Which brings around the next point, filler. Use the baking soda as a filler, run thin super glue over it to solidify it. It goes fast, gets hot and smokes. Anyway, this makes a better filler because it's not as hard as just super glue, which is much harder than styrene and so sanding it ends up with the super glue forming a ridge. But the soda/super glue mix sands down along with the styrene nicely. Also, since there's no solvent to slowly evaporate, it won't end up cracking underneath the paint 6 months later.
Something I have been learning recently is that if there is just a little bit of dried glue on my aplicator, the dab that I have put out on the glass or old spoon (both are great for this), will hardden faster and become unusable. I hypothesize that if there is a little seed of dried CA, it acts to crystalyze faster.
When using for gap filler, as others have mentioned it is very hard. One hint given here before is to begin sanding as soon as you can while it is still workable and has not cured.
Great hint about the baking soda......I am a bit concerned about the heat and the ?? smoke............all those glues seem to be full of carcinogins.........anyway great hint.
I keep two types handy. There is the regular, thin super or crazy glue. This is for joints that fit tightly. I also keep some thick or "gel" super glue. This is for joints that do not fit well, and for wood to plastic joints.
Also, super glue has a limited shelf life. I like to buy smaller amounts than what hobby shops sell. Yeah, it is more expensive than in larger containers, but if you only get half out of the container before it starts going bad, that is not economic either. I buy Elmers brand at local hardware store.
Baking soda can eventually rot and then it oozes out and makes a mess. Best bet is either microballons or resin dust if you want to use an inert filler.
Yeah, I've read someting about using baking soda (many years ago), but I never liked the idea. Somehow using a water soluble substance is not my idea of a premanent glue joint.
It also seems that you don't have much control over the process. The accelerator I use doesn't have as violent setting speed as the baking soda.
Also, the thinner the CA lue, the faster it will "kick over" when using accelerators.
Why not use the chemical specifically designed for the job?
Also, if you sand right after the CA sets, it is still softer than styrene and can be sanded easily. It takes several hours for CA to get harder than styrene.
I'm a very big fan of super glue, and I use it almost exclusively in modeling. My two cents:
- I use worn Badger knife blades (the rounded ones) to apply the glue to the joint. Put a tiny drop on a piece of plastic card, dip the knife blade in it, and transfer it to the joint.
- Be prepared to try a few brands. Some brands can be totally frustrating because of their packaging (I hate tubes for example) and because of the glue's characteristics. I recently tried another CA of my favorite brand, and it didn't work at all for me. My knife blade was glued to the plastic during the dipping for example. So shop around and try a few.
- Don't be tempted to apply the glue to one part, and then press it on the other, that hardly ever works. Hold the parts together, and let the CA flow into the joint. If you're doing a fuselage, work in small distances.
- I also do 90% of my filling with CA. Just don't let it cure too long, otherwise it will be quite hard, harder than the plastic around it.
- I buy the smallest packaging available, 2 grams. This is enough for months of modelling (!) and ensures that you always use fresh glue. It's called a 'droplet pen' here in the Netherlands, perhaps a similar product is available in the US.
PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.