wrote in message
...
Then the following spring I used some of the resin and quickly found out
that it did not cured at all after several days.

Have you tried to put some extra catalyst ("hardener") in the resin?
I bought new resin and it did cured well. Now I have to dispose 1/2
gallon
of resin. Legally I cannot closed the gallon and put it in the garbage.
I
was told that the resin has to solidified before it can be disposed. The
question is how am I going to solidify the un - curable resin already in
the
gallon can?? Conversely I do not have problem with epoxy resin.

Which is logical. Polyester resin only needs a catalyst ("hardener") to
start to cure while with epoxy, the hardener is part of the chemical
reaction to form resin. So without the hardener, there will be no resin.

Meindert