Does CA Go Bad

[jqavins]

Twice recently I've had CA that did not kick in the bottle, but didn't kick on the work either, or did very slowly. First some thin that wicked into a small crack in a case, but took many minutes to cure. Then some thick that wouldn't hold feather stalks together even when sprayed with accelerator. I poured out a dollop of the thick and strayed with the directly with the accelerator: nothing. It did manage to skin over a little later on, remaining mostly as a liquid blister under the very thin cured skin.

It has been through both hot and cold weather without climate control.

Has this happened to anyone else?

 

[o1d_dude]

Yes, CA goes bad.

Some builders store their CA in the freezer to extend the useful life.

 

[rharshberger]

Thats an odd method of going bad..at least to me, normally it thickens in the bottle overtime.

 

[caveduck]

That is truly odd, I've only seen the same expiration mode as Rich. For me, storage life in a fridge is measured in years even for an open bottle, freezer not needed. You might have some defective product there.

 

[jqavins]

I have a few duplicate bottles of that stuff where each store gets own name on the bottle. I'll try another bottle. Or maybe I'll just pitch the lot and get some - what is it? Gold Star? Gold Label? Gold something. Y'know, the good stuff.

 

[neil_w]

SuperGold. Fantastic stuff.

 

[Flyfalcons]

Yes, I have had CA flow normally but not set as quickly as it should. A little CA kicker spray usually does the trick to keep the glue usable.

 

[o1d_dude]

Starbond for the win.

 

[mbeels]

Strange, how old was it? Was it still sealed up, or had the tip been opened? I think temperature cycling may speed up the aging process by helping to pump moisture into the CA.

 

[jqavins]

The thin that failed had previously been opened. The thick had not. I don't know how old, as I have a bad habit of misplacing bottles and buying new ones. I have finally collected all the ones I could find (probably all there are) in one drawer.

Pumping moisture into the bottle should cause it to harden, whereas my problem was failure to kick after flowing out of the bottle. The thin did harden eventually (minutes instead of the scant seconds it should take) and the thick didn't do anything until I sprayed it liberally with accelerator; then it skinned over when it should have virtually boiled and hardened through and fast.

I guess I'll pitch all the bottles of cheap and replace them with SuperGold or Starbond.

OK, next question: SuperGold or Starbond? Two votes are already in.

 

[neil_w]

My old (~3-4 years, dunno exactly) bottle of thin CA definitely cures much more slowly than when new. In fact, I like it much better like that; my new bottle is so fumey and cures so quickly that I can hardly use it for anything. So I'm mostly letting it age until it slows down a bit. Of course, my usage for thin CA is almost entirely for surface hardening; if it loses a bit of bond strength that's fine with me.

I got my SuperGold in a 1 oz bottle instead of my usual 2 oz because at the time it was all eRockets had. In retrospect I'm happy with that choice; I should use that up long before it goes bad. On the other hand, the fact that it is fume-free and can be freely used at any time indoors means I am using it a lot more than I used the old stuff, so I am going through it *fast*.

Presumably the Starbond NO-05 is the equivalent to the SuperGold. That's a pretty good deal, $13.50 for 2 oz plus free shipping. I would recommend against ordering it in the 16 oz or 20 kg sizes.

Addendum: some of the reviews on Amazon suggest that the Starbond is slower curing than the BSI. Just FYI.

 

[Rktman]

I have CA that's closing on 4 years old, and only now is the thin beginning to get gloppy and hardening in the nozzle. However I keep all my CAs in a screw top jar with packets of that silicone moisture-absorbing stuff. Works wonders. It probably helps that the house is air conditioned, at least during the intensely humid summers here.

 

[DaHabes]

My old (~3-4 years, dunno exactly) bottle of thin CA definitely cures much more slowly than when new. In fact, I like it much better like that; my new bottle is so fumey and cures so quickly that I can hardly use it for anything. So I'm mostly letting it age until it slows down a bit. Of course, my usage for thin CA is almost entirely for surface hardening; if it loses a bit of bond strength that's fine with me.

I got my SuperGold in a 1 oz bottle instead of my usual 2 oz because at the time it was all eRockets had. In retrospect I'm happy with that choice; I should use that up long before it goes bad. On the other hand, the fact that it is fume-free and can be freely used at any time indoors means I am using it a lot more than I used the old stuff, so I am going through it *fast*.

Presumably the Starbond NO-05 is the equivalent to the SuperGold. That's a pretty good deal, $13.50 for 2 oz plus free shipping. I would recommend against ordering it in the 16 oz or 20 kg sizes.

Addendum: some of the reviews on Amazon suggest that the Starbond is slower curing than the BSI. Just FYI.

I find the thin CA is really only good for quickly tacking parts in place to check fit, etc., that you can then disassemble. I use medium for what people might normally think they should us thin for, and thick for what people would use medium for. Medium gives you enough time to align parts before it sets. Thick gives you plenty of gap filling if that's what you need. So, for example, I will use medium CA to attach balsa fins to cardboard airframes (LPR) and then fillet with carpenter's glue. Carpenter's glue sets up so slowly that the fins can slip out of alignment without you noticing and then you're kinda "stuck" (pun intended). Not an issue with medium CA. Place fin, hold for 15 seconds, do next fin, continue. Then fillet all fins at once with carpenter's glue. Don't need fancy jigs and such and pretty fast.

 

[neil_w]

I agree, I don't think I ever use thin CA for fastening in that manner, predominantly surface hardening. I did use it to glue a magnet into my eyeglasses. The magnet is a fairly tight friction fit, and then I flowed some thin CA over it to get in the cracks and adhere it. But usually, I would use medium for making one thing stick to another, although that is infrequent.

Lately, my uses for thin are many in LPR building, given that I can do it indoors without noxious fumes:

1. hardening the ends of body tubes
2. hardening balsa nose cones.
3. sealing/hardening the edges of papered fins
4. sealing/hardening paper transition-body tube joints, to prepare for sanding

 

[jqavins]

When I didn't have a jig I attached fins more or less the same way, but I did use thick. Also, before the yellow glue fillets I would add a little thin to wick into the joint, since I only had two drops of thick.

For reasons unrelated to glue my fin mounting was still unsatisfactory, so I'm glad I have a jig.

 

[augendoc]

I bought a kit of woodworker’s Cyanoacrylate made by FastCap maybe fifteen tears ago. Big bottles, about 3-4 oz each, water thin, medium, thick and almost a gel as i recall, with accelerator and debonder. All of them worked great at first. After a few years all the bottles went off and hardened except the water thin one, which stayed water thin but eventually developed a faint pinkish tinge. At this point I could not get it to set, even with accelerator and even when applied iin a thin coat between two surfaces. I threw it out.

I've had Bob Jones Industries medium take a long time to set after it has been opened and aged a bit, but it always went off with accelerator.

 

[augendoc]

Sorry, Bob Smith Industries (BSI).

 

[stantonjtroy]

I use BSI, thick & thin. I've had it fail both ways but always after a year or two and after extensive thermal cycling. I usually use it up before it can go bad but the tube in my range box generally goes after a year or so.

 

[jqavins]

I use BSI, thick & thin. I've had it fail both ways but always after a year or two and after extensive thermal cycling. I usually use it up before it can go bad but the tube in my range box generally goes after a year or so.

Well, that settles it. After a few years of temperature cycling and evidence of slow or non curing, I'm definitely pitching it all.

 

[nelie61]

If your thin CA is not smoking when applied it's getting old (I always wear a mask)and if you guys have it around for that long with the problems mentioned your not building enough models and should only buy the 1/2 oz bottles. I use a lot of CA and thin is by far the most versatile for me for wicking, tacking and coating paper transitions to create a almost plastic transition or boat tail or create a paper nose cone tip filled with epoxy and coated with thin CA. Neil_W Has the best scoop for using CA and we all know the stuff he produces and creates

 

[Rocketjunkie]

I don't use much CA, so I prefer the little 2-3 gram tubes. Once opened, it eventually hardens. Unopened tubes stay fluid.