How old is too old for gallon of 2K urethane?

[mrennie]

I have a gallon of RM DP26 2K urethane primer surfacer and quart of activator that I bought for my project, what I thought was 3-4 year ago...turns out time has gone by faster than I thought, and this stuff was purchased in 2009!

I have opened the primer, and aside from the solids settling on the bottom, once I stirred it for awhile there are no clumps, and it looks good. The activator has never been opened.

So just how stupid am I to entertain using this? If I open the activator and it is not gelled and has no clumps, should I mix a small batch and spray a test panel to see if it is good? Would there be some obvious signs it is junk, and what would I look for?

I need to order more SPI epoxy and am not adverse to buying a new gallon of 2K if required, it's just a bit painful that this RM stuff was $400 for the gallon and activator when I bought it so if it Is reasonable to use it that would be great.

If this is a terrible idea, what the best way to dispose of it? Mix it up and let it harden then send to landfill?

 

[Bentrustynail]

Not stupid at all. I had the same situation, unopened gallon of 2k and unopened activator. It was NINE years old! First I test sprayed it on an old panel. Perfect. Left a free days then I used it on my truck and it sprayed and sanded wonderfully well - just like new. It's been on my truck for a good while now, no issues at all.
I don't think I would have risked the activator had it been opened - certainly not after nine years but it was sealed.

Oh, forgot to add - it was stored in a cool environment the whole time also.

 

[Mike K]

I always flip my old cans twice a year,long as I'm confident in the lid seal.Keeps the solids in a little more mixable shape later.
what the best way to dispose of it? Mix it up and let it harden then send to landfill?
Yeah. Most take solid stuff but liquids are the issue. At least around my parts.