Devcon Epoxy......

[odie]

I am currently using Devcon epoxy in the large bottles, and ran out. I have a couple of new bottles that I stashed away a year, or so, ago. I see the experation date is August 2017. The old bottles are older, and they have been working fine. My question to those who have experienced epoxy going bad from age, is what exactly happens when it does goes bad......?

-----odie-----

 

[billooms]

Mix a small amount. If it gets hard I suspect it's good. I've had some of the Devcon clear epoxy turn a bit more yellow over time, but it always seemed to work fine.

 

[Mike Johnson]

It also depends on the environment it was stored in and transported in after production.
Like any other product the expiration date usually has a fudge factor to take those variables
into account. Storing a product in a stable environment without daily temperature swings usually
increases the shelf life of a product.

 

[Bill Boehme]

I've kept some in the refrigerator for several years and it worked fine. I've also had some go bad very quickly in a hot garage. If my memory is correct, the resin gets too thick to be usable. The useful life also depends on what you want to do with it. For inlay work I would only use fresh glue.

 

[Zach LaPerriere]

I'm not familiar with the DevCon but for boat work I've used West System and System 3 that is very old . When I've talked with the tech reps they suggest discoloring is natural, but as Bill says, it it's hasn't thickened it's deemed good to go—at least for non-critical glue ups.

I was recently gifted a bunch of mismatched epoxies that were purchased at garage sales 10 to 15 years ago. I only mixed epoxy from the same manufacturer, and it all hardened well.

 

[Arkriver]

Somewhere along the line I heard that the half lif of epoxy and spaghetti sauce was eternity. I have some epoxy that is well over 10 yrs old and still works fine. Mix some up and use it on some scrap if in doubt.

 

[Lamar Wright]

Odie, I've had a little experience with Devcon used it in my pen work. If the hardener looks sort of granular and chunky it is probably bad. When mixed the results will be small voids and soft spots in the cured mix. I wouldn't judge it by the date, if the hardener is smooth and creamy it is fine. I would test it first. Happy turning.

 

[John Torchick]

As mentioned, mix a small amount and watch it.

 

[Owen Lowe]

Odie, I've had a little experience with Devcon used it in my pen work. If the hardener looks sort of granular and chunky it is probably bad. When mixed the results will be small voids and soft spots in the cured mix. I wouldn't judge it by the date, if the hardener is smooth and creamy it is fine. I would test it first. Happy turning.

West Systems website has (had?) a good FAQ that addresses life and crystallization of the resin & hardener. As I recall they say that essentially there is no expiration for the two chemicals. If you see crystallization, put the container in a hot water bath until the crystals dissolve and then use as normal. Crystallization is a common occurrence in storage and won’t harm the reaction or strength of the cured epoxy.

 

[Leo Van Der Loo]

I was given a half dozen tubes of 3M epoxy that where each actual 2 tubes with the parts of the epoxy, these had red stickers on them with an expiry date on them, as the epoxy was to be used on some satellite parts, the epoxy was discarded and that’s how I got them, these are better than 10 years old by now, and I still have some of it, used it last a couple of months ago, it has gotten quite hard to press it out, but it still works fine,

Warming it up makes it thinner, but it also speeds up the hardening, as that was done to shorten the time these units had to sit before the next step in the process could be done.

So I guess like Owen is saying, it does not really expire for a long time.

 

[Mike Johnson]

Expiration dates are a commonly used sales and marketing strategy used in commerce.
There are plenty of crazy items that list expiration dates on the packaging.

 

[odie]

Expiration dates are a commonly used sales and marketing strategy used in commerce.
There are plenty of crazy items that list expiration dates on the packaging.

I can definitely see how that could be a strategy......if a prior customer threw away the unused portion, and bought more, thinking it's more likely to avoid any failures......

-----odie-----

 

[Raul McCai]

I have a love hate relationship with epoxy. I've used several kinds and had a variety of different results.
I've had it
1) literally go to garbage a year or two after the joinery was finished. Just crumbled into gooey crumbly worthless garbage.
2) Total joint failure from squeeze out
3) way too often it's been less strong than the wood being glued
4) yellowing
I've also had good results and I have a Novalac Epoxy potted item with cross sections almost an inch thick made for a medical pH Blood Gas Chromatograph machine that I was designing stand up for decades. Still have a sample on the shelf behind my desk. Not a single flaw anywhere in it.
Like I said Love Hate.


I've come to not trust the stuff.

 

[Owen Lowe]

I think the bottom line with epoxy performance is to choose a highly-regarded manufacturer, like West Systems in the US, that has a long track record and has a customer service presence that can assist with problems. They’re not inexpensive products, but what you get is consistency and a complete line of compatible products to address a vast array of epoxy situations. (Their main focus is boat building and refinishing which equals high dollars and picky end-users, so their reputation is very much at stake regarding performance and reliability.)

As an aside, West Systems is very specific about mixing ratios in their instructions. When we turners are mixing small batches of epoxy using the about-the-same-size-puddle method I believe that potentially introduces performance and consistency issues that the manufacturer has no control over.