MikeyDSlagle
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- Dec 16, 2013
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So I have been using US Composites 150 for a couple of years now. I always recommend it. Recently I got some of their 635 thin epoxy with 3:1 hardener (medium) to try with chopped fiberglass and possibly for sealing/strengthening/hardening MMTs and BTs and fins. My thinking is the stuff absorbs into the material just like CA does. I see it soak out around my internal fillets and harden the surrounding area.
So here is the problem. This 635 stuff will not cure. I laid some fillets with chopped fiber (right after I recommended it to another user) and after 6+ hours it was only a bit tacky so I rolled my fin can to do another set. By the time that set was tacky, another few hours, the first set had drooped. And it still had visible air bubbles. I scraped all that off and used the 150 stuff as normal and it set up with no issues. Thought maybe it was an issue with the thick fillets causing the epoxy to take time to set. So...
I went ahead used it to harden a MMT and a scrap piece of wood. This was last night, about 7pm. It is still tacky. I have had it under two lights, in the kitchen, for 3 hours now and it is STILL tacky. The website says 8 to 10 hours drying time for the 3:1 hardener. Shouldn't matter if it is thick or thin.
Is this normal for 635 epoxy?
Is it just super slow to fully cure?
I thought maybe the humidity, dew point, temp, pressure, something was affecting the cure, but like I say. They 150 cured just fine.
I am going to shoot them an email. Just wanted to see what you folks thought. And see if anyone has similar experiences.
Thanks,
Mikey D
So here is the problem. This 635 stuff will not cure. I laid some fillets with chopped fiber (right after I recommended it to another user) and after 6+ hours it was only a bit tacky so I rolled my fin can to do another set. By the time that set was tacky, another few hours, the first set had drooped. And it still had visible air bubbles. I scraped all that off and used the 150 stuff as normal and it set up with no issues. Thought maybe it was an issue with the thick fillets causing the epoxy to take time to set. So...
I went ahead used it to harden a MMT and a scrap piece of wood. This was last night, about 7pm. It is still tacky. I have had it under two lights, in the kitchen, for 3 hours now and it is STILL tacky. The website says 8 to 10 hours drying time for the 3:1 hardener. Shouldn't matter if it is thick or thin.
Is this normal for 635 epoxy?
Is it just super slow to fully cure?
I thought maybe the humidity, dew point, temp, pressure, something was affecting the cure, but like I say. They 150 cured just fine.
I am going to shoot them an email. Just wanted to see what you folks thought. And see if anyone has similar experiences.
Thanks,
Mikey D