C & E wrote:
I had bought a small bottle of Sumo, urethane glue about 8 months ago and
found a project for it today. I was shocked when I found the bottle to be
firm and, when I opened it the glue was more firm than usual. I got what I
needed and pitched the rest. That was a pretty expensive bottle considering
that I only got one use.

Finally, the question. What IS the shelf life of **unopened** urethane
glue? I had a similar sized bottle of Gorilla Glue and it lasted much
longer even though it had been used and there was air in the bottle. I did
store it on its head but still...

TIA,
Chuck


Traces of moisture will cause isocyanate glues to gel. Even plastic is
permeable even when tightly sealed. I would expect an expiration date
for unopened material.