How to tell if resin is old?

General Discussion
1

How can you tell if polyester resin is old?

It takes approximately 6 months before polyester resin starts to be unuseable, correct?

“old” resin that shouldn’t be used is yellowish is color rather than green, or so I understand.

I have a bottle of resin in my garage that is about a year old, but the resin is still green. I would use this resin for a hot coat.

Should I use it?

2

if in doubt , throw it out .

Plan B …got any spare bits of foam lying around ?

If so … do a test using that … laminate , then use the ? suspect? ‘hotcoat’ resin . See how it goes…

just a thought

‘chip’

3

So when I test it, if the resin is clear when it dries, I can use it? And if it turns yellow when it tries, I shouldn’t?

4

i generally go by taste. if it’s got the funk of week-old socks, then it’s no good.

5
Quote:

So when I test it, if the resin is clear when it dries, I can use it? And if it turns yellow when it tries, I shouldn’t?

if it tries to yellow , stop it ! [tint yellow to be on the safe side ]

hope this helps

ben

6

,the first you see is that the resin turns to gel…i mean, less liquid, more like gelatin thing…