THRILLSEEKER

I've got some VE resin and MEKP from U.S. Composites that I've had since last late last summer and it was'nt cracked open until late Nov. 12.

How serious are they when they say the shelf life is 3 months un opened?

Do I need to ****can this stuff and buy fresh, or is it still OK to use?

modvp

From what I can remember the shelf life is about 6 months.

skaterdave

really depends on how it was stored. humidity and the temp are the biggest factors.

the resin has a pretty good shelf life were as the hardner goes bad alot quicker. might try making up a sample and seeing if it kicks off. or maybe just try new hardner.

c_deezy

iTrader: (1)

I've used old resin before. Stir it or shake it up, then do a test batch like mentioned above and see what happens.

What I've found is that older stuff does take a little longer to go off sometimes, but it does go off.

glassdave

iTrader: (1)

what are you doing with it? I would say if you are doing a structural repair of something on the running surface i would get new just for piece of mind, Beyond that as said above just do a test layup.

ren3

I have used resin on non structural projects that was four years old, but it was stored very cool and sealed. It was just an experimentbut worked great. I bought vinylester and gel coat from US Composites, and did not use it for three months, and I was disappointed at the quality of cure of both. I know that some of the problem was a temperature of only 70 degrees, but I use other suppliers and will not use USC again. I find that Riechol (sic) vinylester to be far superior in curing and shelf life. I use iso gelcoat that is available locally with a freshness guarantee. I can only assume that there is a vast quality difference in available chemicals, and a corresponding lack of tracking on age since manufacture and shelf life. I think that very few sellers actually know or care.

THRILLSEEKER

Its going for transom patching where the K Planes/5200 ripped off several layers of matt. I'll try a test batch and see what happens. Thanks for the advice guys.

skaterdave

next time use some heat on 5200 sealant. loosen it right up

Rick G

Polyester resin if stored in a sealed container in a cool dry will last for quite some time , it needs to be mixed before use and you can use acetone to thin it if it has thickened over time. I agree I would NOT use realy old resin for anything structural . Vinyl ester resin has chemicals added to it when it is readied for sale( I believe cobalt is one of them ) . I purchase my VE resins from composites Canada and they informed me that it is pretty much useless after six months regardless how it might be stored because the chemicals that are added begin to break down.
Rick G.