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Jeff Liebermann Jeff Liebermann is offline
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Default What is the shelf life of common adhesives?

On Thu, 25 Jan 2018 19:09:47 -0800 (PST), Terry Schwartz
wrote:

I'd bet the manufacturers web sites would have information
on shelf life. Double what they claim, and you'll have
a more realistic number.


Double of what claim? I can't seem to find shelf life, or how long it
lasts after it's opened, for most adhesives. Have you actually
experienced double an unstated shelf life?

Refrigeration extends the working life of most adhesives.


As Phil mentioned, that doesn't work. I've tried the same thing with
RTV (silicone seal) caulk tubes. It's about the same with or without
refrigeration. It lasts about a year no matter what I tried. For
example:
http://www.accumetricinc.com/uplimg/dynatex/tds/49274.pdf
"When stored in the original unopened containers
at or below 90°F (32°C), Dynatex ® Clear
Silicone Adhesive/Sealant has a shelf life of 12 months
from date of shipment."
That means if it's been sitting around collecting dust at the hardware
store for 6 months, you might have 6 months of useful life. If you've
used the tube, it's likely to be less than 6 months.

I appreciate your comments, but it would be more helpful if you
provided your experience with adhesive shelf life and lifetimes rather
than guessing what it might be under contrived circumstances.

Update: The JB Weld KwikWeld didn't hold. Instead of drying hard as
the proverbial rock, it dried into something more like hard rubber.
Apply a bit of force to the hinges and it fell apart. I also bought
some Devcon 2 ton epoxy. However, when I tried to squeeze out the
resin, I found it to be crystallized in the tube. I mixed it anyway
to see what would happen. The result was something that looked like
hard styrofoam, full of air/gas bubbles. Useless.

I just found a "new" tube of Ace Hardware 24 hr epoxy that looks good.
Hopefully, it will hold together. This is getting ridiculous.


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