Does Fiberglass resin go bad?

[69a100]

I have about as much hardener as I do resin and after 1.5 hours, it's still gooey. I have even used heat to help expedite drying to no avail. What gives?

 

[WileERobby]

I haven't glassed in a while, but do you mean the materials are "old" ? Like, been sitting somewhere for years ? If it's polyester resin, it's probably bad if it's old.

 

[69a100]

It's old and been sitting, I don't know if it's poly or not? The jar doesn't say. SUCK, what are my options to get it cured, if any?
I guess the only other option is to make a mess and wipe it all down and do over with fresh/new stuff? I'm doing this on a old kitchen cabinet so perfection and looks aren't a high priority

 

[eldubb440]

you may have used too much hardner

 

[69a100]

I followed directions and it didn't harden. I added more resin and stirred/mixed after already laid out and still no effect. I did that twice before saying screw it and just dumped the rest of the hardener. Still nothing, took the heater came out and still no help.
One or the other is bad I'm guessin?

 

[Photon440]

I have about as much hardener as I do resin and after 1.5 hours, it's still gooey. I have even used heat to help expedite drying to no avail. What gives?

Were you mixing up polyester resin or epoxy resin? Polyester resin (the type normally employed for fiberglassing) usually needs only about 1% hardener, less in larger batches. For instance a gallon of resin would use one ounce of hardener.

But epoxy resin usually has a 1:1 mix ratio, which sounds like what you were doing. Epoxy resins are usually quite sensitive to cooler temperatures and if below about 70 degrees often don't set up at all. Adding heat later may be too late. Also, check with the brand you're using as often the epoxy cure time can take from 24 to 72 hours before it's really hard. There are some types of epoxy that require much higher temperatures, over 100 degrees.

 

[69a100]

The last time I used it, I have no idea when that was? It would harden up within 10 minutes. I'm doing this inside but it's above 70*.

 

[Slap Stick]

It may be the hardener has gone bad but I dunno if that can happen, either.

 

[69a100]

It may be the hardener has gone bad but I dunno if that can happen, either.

I hardly had any in the old bottle, so I bought & used a new tube of hardener. The next question would be, were they compatible to do the job? This morning it's a little tackier, so maybe by the end of the week it'll be reasonability cured?

 

[cr8crshr]

What are you using it for Bro??? cr8crshr/Bill

 

[Photon440]

You didn't mention whether it was polyester or epoxy resin that you were using.

 

[Curiousyellow71]

I had the same thing happen. It was old resin and it remained tacky it never fully cured. So, I would concur resin can go bad with age. As to what type of resin I had...not sure.
...I had to grind the old off and start over...not fun.

 

[Cranky]

You didn't mention whether it was polyester or epoxy resin that you were using.

He said he didn't know if it was poly or not.....

 

[69a100]

He said he didn't know if it was poly or not.....

What are you using it for Bro??? cr8crshr/Bill

Encapsulating the mold damage under the sink.

 

[sam dupont]

Had gel coat do it to me. I bought a quart at a boat shop,, but they didn't have any hardener, so I bought some elsewhere. I assume the hardener was not compatible as it didn't set, but haven't been back to the boat shop to get the stuff I know will be compatible

 

[Photon440]

He said he didn't know if it was poly or not.....

Well, he said he got more hardener, he'd need to know what type.

 

[Tony Tee]

If it's polyester? The catalyst may have gone bad. If it's epoxy? It might have absorbed too much moisture . If it smells like bondo it's polyester. If it kinda smells like dead fish (sometimes) it's epoxy. If you can't smell anything? its covid. LOL! Buy some new resin whatever you have ? It's gone bad.

 

[bandit67]

I think I remember with the polyester resin mixing was 10 drops hardner per ounce or resin. I used some pretty old stuff once and it took about two weeks to hardened up, but it did. Not sure just how old it needs to be to trash it for sure. If you have time, put it in the sun if possible and wait a bit longer.....

 

[69a100]

You didn't mention whether it was polyester or epoxy resin that you were using.

Well, he said he got more hardener, he'd need to know what type.

Just go RE-read post #3, I was clear about that!

It's old and been sitting, I don't know if it's poly or not? The jar doesn't say.

 

[super-bee_ski]

It's old and been sitting, I don't know if it's poly or not? The jar doesn't say. SUCK, what are my options to get it cured, if any?
I guess the only other option is to make a mess and wipe it all down and do over with fresh/new stuff? I'm doing this on a old kitchen cabinet so perfection and looks aren't a high priority

POST NUMBER 3 explains OPs issue