Prowline Epoxy

Well, being LDRS this year conflicted with my wife' class reunion and I was unable to attend my preference, I decided to start a build today, (Gismo).

Having a virgin gallon can of Pro-Line epoxy resin and hardener that has been sitting in the hobby room for several years, I decided to use it for this build rather than use my normal epoxy, West Systems. Unfortunately, when I cracked open the resin can, it appears that some of the resin, (about half the can), had solidified. However, the hardener appeared to be ok. I mixed a small test batch and allowed time for cure and it cured solid under a heat lamp in roughly 30 to 40 min.

Has anyone else experienced this issue with Pro-Line epoxy? Being I have had this epoxy for well over 4 years, this may just be a shelf life issue.

Most of the laminating epoxies I use have an advertised shelf life of around a year. I have gone past that more than once but had there been problems I would not expect anything from the manufacturer. I have seen what you are describing and the epoxy was made usable again by heating the resin in hot water (very hot). I have heard of people heating it in a microwave but that does not seem a good idea to me. It will give off fumes if you heat it so beware. I doubt Pro-Line will endorse this approach so you're on your own if you try it. I know a gallon of epoxy is a decent investment these days but even if I could get it to go back liquid I would not use it in any high stress areas. George

It should liquify in boiling water. happens when it gets cold.

QUOTE=gltruett;734310]Most of the laminating epoxies I use have an advertised shelf life of around a year. I have gone past that more than once but had there been problems I would not expect anything from the manufacturer. I have seen what you are describing and the epoxy was made usable again by heating the resin in hot water (very hot). I have heard of people heating it in a microwave but that does not seem a good idea to me. It will give off fumes if you heat it so beware. I doubt Pro-Line will endorse this approach so you're on your own if you try it. I know a gallon of epoxy is a decent investment these days but even if I could get it to go back liquid I would not use it in any high stress areas. George[/QUOTE]

Thanks for the response... Not looking or expecting anything from the manufacture, as I know this stuff is well past any shelf life... I just might try the hot water method... Forgot about the old hot water trick... Used to use boiling hot water on paste type epoxy resin that had gotten stiff.

Fred, I had the same problem. I was able to put the can of resin into a sink of hot water for an hour or so, which dissolved it back to a liquid. I have had no issues with it after doing this, and I like it almost as well as Aeropoxy.


Mark Koelsch
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My can of West did this too. My oven goes down to 175 degrees, so I put the steel can in there for 10mins. Worked great. Never re-solidified.

Adrian