Does CA glue go bad??

[Brutalform]

Today I was trying to glue a MAD distributor cap on the base. It usually grabs permanently with just a tiny dab. I was using Zap medium, just as I have always. Even after applying Zipkicker it still wouldn't hold. Does CA glue expire, or go bad? 

[Ace-Garageguy]

 Does CA glue expire, or go bad? 

Yes. definitely.

It varies from product to product. I've had some that's useless one month after opening, and some of the Loctite stuff has lasted for years...though it doesn't work as well as it ages.

[Mooneyzs]

I will agree with Bill here, It will go bad.  One thing that I typically do is when I don't use my CA... Most of the time I keep it stored in my freezer... down side is that when you want to use it you need to let it thaw out but it does help it last loner. I learned this trick from my dad years ago, He did that when building his R/C Airplanes.

[Snake45]

Funny you should ask. I've been using a two or three year old tube--opened for the first time just recently--and it was working fine. And then I went to glue something with it Sunday, and I held the thing and held it and held it, and nothing at all seemed to be happening. I finally gave up and glued the joint with Testor liquid, though it didn't do as clean a job as the CA would have, if it had worked.

Walmart USED to sell four tubes of generic CA in a blister pack, very cheap, and the stuff worked good. But I've been looking for that again for the last month and they don't seem to have it anymore.

[Ace-Garageguy]

I should have been clearer.

The shelf life is generally considered to be about one year unopened (though this can vary widely, and it lasts almost indefinitely if it's refrigerated before opening), and about one month after opening.

Again, it really depends on the specific product and how it's handled and stored.

[slusher]

Yes. definitely.

It varies from product to product. I've had some that's useless one month after opening, and some of the Loctite stuff has lasted for years...though it doesn't work as well as it ages.

if you ever leave the cap off it weakens. I use Loctite 495 and it's great stuff. I have had it a long time. I bought it on eBay but should be sold in hardware stores..

[Howard Cohen]

Super glues are meant to air dry, so every time you open the tube/bottle/whatever, a bit of air gets in and starts the drying process. I have several large bottles and recently found they dry out. I switched to small tubes of Gorilla Super Glue. 

[bobthehobbyguy]

Actually super glue dries because of moisture it the air, it was designed ti be used for stiches and that why it glues your fingers together so well.

[Brutalform]

Thank you for the replies. I have a Zap Thin that's unopened. I've had it for two years so I'll give it a try before tossing it. The medium is as just as old. I guess I'll have to find some smaller bottles, and keep them in the freezer also. 

[plastic-mechanic]

Super glues are meant to air dry, so every time you open the tube/bottle/whatever, a bit of air gets in and starts the drying process. I have several large bottles and recently found they dry out. I switched to small tubes of Gorilla Super Glue. 

i think most CA type glues are anaerobic

[Ace-Garageguy]

i think most CA type glues are anaerobic

Actually, no. "Anerobic" means "in the absence of air". CA WILL cure in air, because of the moisture present.

Loctite's thread-lockers are all true anerobic adhesives. CA is not.

But don't take MY word for it. From the IPMS / Stockholm site:

 

"A common source of confusion is mixing up CA glue with Locktite thread locking glue. The main reason for this seems to be historical. The Loctite brand that initially produced the thread locking glue became for many users synonymous with that type of glue. Nowadays, Loctite has an entire variety of glue products in its range, CA glue among them. The main difference between the two types is in the medium activating the bonding reaction. In the thread locking glue, polymerisation starts in the absence of oxygene (air), while CA bonds with the aid of humidity.

How it Works

The cyanoacrylate glue hardens very quickly when trapped between two surfaces. The reaction is caused by the condensed water vapour on the surfaces (namely the hydroxyl ions in water). The water comes from the surrounding air, so obviously the air humidity is a factor that may affect bonding capabilities, or cause them to differ from application to application.

The curing reaction starts at the surface of the bonded material and develops towards the centre of the bond. Because of this, thick seams or large blobs of glue may harden less satisfactorily than surface-to-surface bonds with good fit. In a thick blob of glue, a polymerisation reaction may stop before it reaches the centre of the blob. A rule of thumb is that seams thicker than 0,25 mm should be avoided. Thick seams will also take longer time to cure.

The described relation between seam width and curing time can be used to advantage: a thick superglue-filled seam will allow adjustment of the parts, but will bond instantly and definitely when they are pressed together, so that the gap decreases below 0,25 mm. Pressing the parts harder against each other will make the glue cure instantly."

Edited September 22, 2016 by Ace-Garageguy

[plastic-mechanic]

see how easy it is to have somebody else do the heavy lifting?

[Ace-Garageguy]

see how easy it is to have somebody else do the heavy lifting?

Yeah. Just put up a response based on ignorance, misunderstanding, or pure uninformed conjecture.

Some adult will come along and clean up the mess.  

[peteski]

CA glues do not "dry" - they harden by a chemical reaction (they polymerize). Moisture will cause them to slowly harden - if you have a new unopened tube or bottle and the moisture doe s not penetrate inside then the glue will remain usable for many years.  But once you open the bottle the moisture from the ambient air will get in and will slowly cause the glue to thicken up (it is not thickening because a solvent is evaporating).  Some good info is at https://en.wikipedia.org/wiki/Cyanoacrylate .

CA adhesives have a short shelf life. Date-stamped containers help to ensure that the adhesive is still viable. One manufacturer supplies the following information and advice:

When kept unopened in a cool, dry location such as a refrigerator at a temperature of about 55 °F (13 °C), the shelf life of cyanoacrylate will be extended from about one year from manufacture to at least 15 months. If the adhesive is to be used within six months, it is not necessary to refrigerate it. Cyanoacrylates are moisture-sensitive, and moving from a cool to a hot location will create condensation; after removing from the refrigerator, it is best to let the adhesive reach room temperature before opening. After opening, it should be used within 30 days. Open containers should not be refrigerated.^[30]

Another manufacturer says that the maximum shelf life of 12 months is obtained for some of their cyanoacrylates if the original containers are stored at 35 to 40 °F (2 to 4 °C).^[31] User forums and some manufacturers say that an almost unlimited shelf life is attainable by storing unopened at −4 °F (−20 °C), the typical temperature of a domestic freezer, and allowing the contents to reach room temperature before use.^[32] Rechilling an opened container may cause moisture from the air to condense in the container; however, reports from hobbyists suggest that storing CA in a freezer can preserve opened cyanoacrylate indefinitely.

As cyanoacrylates age, they polymerize, become thicker, and cure more slowly. They can be thinned with a cyanoacrylate of the same chemical composition with lower viscosity.^[33] Storing cyanoacrylates below 0 °F (−18 °C) will nearly stop the polymerization process and prevent aging.

 

One thing that is puzzling is that I have never seen CA glue going "bad" where it is still as liquid as expected but even the accelerator will not cause it to harden. In my experience (as mentioned above) I have only seen CA going bad by thickening or totally solidifying in its container.

Edited September 22, 2016 by peteski

[Dennis Lacy]

I use Zap-A-Gap primarily and anymore I will only buy the smallest bottle. Anything more is a waste of money because the stuff goes bad faster than I can use it. I have found that once opened I can get about 4-6 months of satisfactory use before there is a noticeable decline in performance. I usually find out the stuff has gone bad when it's most inconvenient, too.

There's few things more satisfying to a model builder than a brand new, freshly opened bottle of CA. 

Edited September 22, 2016 by Dennis Lacy

[timc]

Well I might be the exception. I have been using the same bottle of loctite 454 for about 4 years now. No problems with it that I have noticed. It is the industrial thick gel type. I put what I need on an old pringles lid and close the bottle immediately. Then I use tooth picks to apply it to parts. It dont fog chrome or windows either. Might be hard to find outside of industrial suppliers.

[iamsuperdan]

I was wondering about this exact thing recently, as the bottle I have on the go just isn't working anymore. Ahh well, just another excuse to head to the hobby store!

[plastic-mechanic]

Yeah. Just put up a response based on ignorance, misunderstanding, or pure uninformed conjecture.

Some adult will come along and clean up the mess.  

my word, man. what did your parents do to you?

[Ace-Garageguy]

my word, man. what did your parents do to you?

And this remark helps the experience people have here on the forum exactly how?

It's even more useless than your "i think most CA type glues are anaerobic" remark, founded on no actual factual information whatsoever.

I do wonder why you seem to have the need to make these sideways personal attacks.

In case you haven't heard, Harry has quite enough to deal with without having to get involved with chimps throwing poo around, so why don't you just get over it and try acting like an adult.

YOU are the one who ALWAYS starts in on the personal remarks and comments calculated to get a rise out of people, and it really needs to stop.

Edited September 22, 2016 by Ace-Garageguy

[Ace-Garageguy]

Well I might be the exception. I have been using the same bottle of loctite 454 for about 4 years now. No problems with it that I have noticed. It is the industrial thick gel type. I put what I need on an old pringles lid and close the bottle immediately. Then I use tooth picks to apply it to parts. It dont fog chrome or windows either. Might be hard to find outside of industrial suppliers.

I've also had good luck with the thickened Loctite products lasting much longer after being opened than the 'regular' little-tube CA adhesives, but in my experience, the performance does degrade over time.

[Brutalform]

CA glues do not "dry" - they harden by a chemical reaction (they polymerize). Moisture will cause them to slowly harden - if you have a new unopened tube or bottle and the moisture doe s not penetrate inside then the glue will remain usable for many years.  But once you open the bottle the moisture from the ambient air will get in and will slowly cause the glue to thicken up (it is not thickening because a solvent is evaporating).  Some good info is at https://en.wikipedia.org/wiki/Cyanoacrylate .

CA adhesives have a short shelf life. Date-stamped containers help to ensure that the adhesive is still viable. One manufacturer supplies the following information and advice:

Another manufacturer says that the maximum shelf life of 12 months is obtained for some of their cyanoacrylates if the original containers are stored at 35 to 40 °F (2 to 4 °C).^[31] User forums and some manufacturers say that an almost unlimited shelf life is attainable by storing unopened at −4 °F (−20 °C), the typical temperature of a domestic freezer, and allowing the contents to reach room temperature before use.^[32] Rechilling an opened container may cause moisture from the air to condense in the container; however, reports from hobbyists suggest that storing CA in a freezer can preserve opened cyanoacrylate indefinitely.

As cyanoacrylates age, they polymerize, become thicker, and cure more slowly. They can be thinned with a cyanoacrylate of the same chemical composition with lower viscosity.^[33] Storing cyanoacrylates below 0 °F (−18 °C) will nearly stop the polymerization process and prevent aging.

 

One thing that is puzzling is that I have never seen CA glue going "bad" where it is still as liquid as expected but even the accelerator will not cause it to harden. In my experience (as mentioned above) I have only seen CA going bad by thickening or totally solidifying in its container.

After removing the cap, and sticking a pin into the applicator, I will get liquid CA glue from the bottle. After its applied to the work, it will not bond. Even after applying kicker, it seems to bond slightly, but, as soon as its touched, the part will fall off.

[Brutalform]

Well I might be the exception. I have been using the same bottle of loctite 454 for about 4 years now. No problems with it that I have noticed. It is the industrial thick gel type. I put what I need on an old pringles lid and close the bottle immediately. Then I use tooth picks to apply it to parts. It dont fog chrome or windows either. Might be hard to find outside of industrial suppliers.

I always do the same, with a lid, or piece of shiny cardboard. I NEVER work from the bottle directly. Always close it up immediately.

[Brutalform]

I opened the new bottle of thin ZAP and tried it.  This bottle is a few years old as well, just sitting on the shelf. I'm sure the shelf life contributed to the glue breaking down, as it acted just as the medium when used. These bottles are only 0.5 oz. I don't think I can buy them any smaller than this. off for some new CA. Thank you for all of the replies everyone. Much appreciated.

[Mike999]

FWIW, I've been using the same 3 bottles of CA for a year now; 1 each of Thin, Thick and Medium.  This is the "Extreme" brand, sold at Hobby Lobby. All seem to be still working good without any special handling. I just keep them on the workbench in my basement. 

The biggest problem I have is the one that everybody probably has - hardened glue build-up on the applicator, so the top no longer fits tight. 

[TarheelRick]

FWIW Harbor Freight sells .1 oz tubes 10 to a pack for less than $2-3 especially if you use their 20% coupon.