PVA glue shelf life test

Referring to Triton glue here which I take to be PVA.

Was going to toss the bottle that I'd marked '06 but why not test it first.

Butt joined with the glue the edges of two pieces of softwood, 130mm long, 80 wide and 21 thick.

After 24 hours I held the bottom half in the vice and pulled hard with both hands on the top piece. No failure. Then thumped the top half with the palm and got separation, but the wood failed, not the glue.

The stuff has been stored in the workshop which gets to 40º sometimes, but there wasn't much of it used so little airspace.

Interesting result and a worthwhile delaying tactic before I tackle the Xmas family lunch dishes :U

From my experience, as long as your PVA still looks OK, it should be right to use. Once it goes begins to look like cottage cheese, you better hit the shops.

Ern, I've had a few bottles go 'off' after a couple of years. If the consistency is normal, everything seems to be fine, but the warning sign is when they start looking a bit ropey, as GG says. It will definitely NOT form anything like max strength then. Discovering this caused me some severe embarrassment & inconvenience on one occasion :C . Prior to that, I never worried about shelf life, though was aware that it was recommended to not keep it longer than a year. I kept some for MUCH longer than that, and the glue still seemed to work, too, so I just assumed the stated shelf life was a cynical bid to have us buy more....

I've not seen any warnings that high temps accelarate deterioration in the bottle (heat does reduce open-time, of course), but just about every botle I've seen warns against freezing, which must be an occasional concern at least, down your way. I don't take risks with it any more. I use little PVA type glue anyway, so buy in small quantities, date it, & chuck out what's left after 18 months max. Glue is the least expensive 'consumable' in my shed......

Cheers,

I have a bottle in my cupboard at least 8yo. Do I chuck it????

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Originally Posted by cookie48

I have a bottle in my cupboard at least 8yo. Do I chuck it????

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8yo! :o Are you looking to set the record, Cookie? :U
If it still looks smooth & liquid, it MAY be fine, but I sure wouldn't trust it with my life.......

While the "one year" shelf life that is typically recommended may be very conservative, this stuff does go off, sooner or later, I don't think anyone can deny that. I'm as tight as a fish's rear orifice myself, & hate wasting anything, but I hate glue failures even more, so after my couple of bad experiences, I tend to err on the very cautious side. :;

Cheers,

I use bostitch av180 yellow glue. I buy that in 5L bottles that usually last me around three years or so. I keep the big bottle capped, but the small bottle uncapped and have never had any of that go off. The official talk says that it has a 12 month shelf life.

Hope this sheds some light.

Robert

I agree Ian that for a want of a nail the battle may be lost.

This bottle won't get any important use and the test was just done out of interest given prior posts about shelf life.

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Originally Posted by rsser

I agree Ian that for a want of a nail the battle may be lost.

This bottle won't get any important use and the test was just done out of interest given prior posts about shelf life.

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Ern - yairs, I think yours and other posts help make the point that shelf life is a very moveable feast with PVA glues. If you knew the chemistry of the stuff intimately, you could probably suggest good reasons for this, but I don't. I know its not restricted to a single brand or type, because I've had 3 different types go off, the latest being some Titebond II, about 15 months after purchase. (I would normally not have it that long, but I seem to use less & less of it, these days). This particular bottle could easily have been old stock when I got it, so I'm not suggesting it's necessarily the fault of TB. I went to use some one day and noticed it had gone 'ropey' in the bottle, and given my prior bad experience, I didn't even try to stick anything with it, I promptly chucked it.

Specialist: Quite a few years ago, the wood club I belonged to used to buy AV180 in large quantities & we divvied it up in smaller batches. I used to take 2L at a time, put some in a dispenser, as you do, and put the rest away in a cupboard til a refill was neeed. It used to take me a bit under 2 yrs to go through a couple of litres, and I didn't run into any problems until I started using it up more slowly, and had half a bottle go off. That was when I first found out why it's not a good idea to use stringy PVA glue!

Storage conditions probably make a big difference to shelf life. Said bottle of Titebond sat most of the time on a shelf just inside a window, and it's quite possible that accelarated its demise. I think the points people need to be aware of are:
1. Shelf life of PVA is variable, but it WILL, definitely, detereiorate over time.
2. The factors that influence shelf life are unknown to me (& if anyone has certain knowledge, please inform us!).
3. If you notice any texture changes in your glue, it has almost certainly gone off.

As I said, I reckon that for the sake of a few $$ worth of glue, it's better to replace old stuff regularly, rather than risk failure (unless you are building a boat for your MIL to sail in shark-infested waters.... :;).

Cheers,

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Originally Posted by IanW

As I said, I reckon that for the sake of a few $$ worth of glue, it's better to replace old stuff regularly, rather than risk failure (unless you are building a boat for your MIL to sail in shark-infested waters.... :;).

Cheers,

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P'raps better to use Clag or UHU on WOW boat?:D:D:rolleyes: