Second try here, lost first post trying to shrink photo.
Anyway, tried to post cure epoxy in black bag in sunshine. Temp was around 125 degree F for about 4 hours. I’m using med cure thin epoxy from us composites with some additive F from resin research. Lam was 7 day cure, hot coat 3 day cure, gloss was 16 hours then black bagged.
This as a good lam job, no air, but the box was a little oversized but was fillled in with resin. So does my resin suck? Is high temp post cure a bad idea?
This happened once before on a home made blank (partA,B, pour foam) that had a poorly repaired slit that split open when the board was left in sun a couple of hours. Blank also had lots of air pockets in foam. But this current blank was a first quality us blanks green foam.
Now, instead of sanding down and surfing I have to go cut, repair, and what, wait another week? Slightly bummed…
What’s the problem?
Mahalo
Quote:
What’s the problem?
Mahalo
Not trying to be a wise guy, but what is the problem? You have an air pocket, but where, and in what? The blank, or the glass job?
possibly overcured and you got delam?
Not sure what part of the world you are from… Your profile doesn’t say.
I’d be real careful post-curing that way. Just because over here (South Australia) a black bag can easily get hot enough to cause delams.
How warm did it get on that day?
Well, here it is.......I really feel stupid now. Went out and cut out the glass. What happened was the entire box came loose because I eye-balled the resin mix. It was left over and too low in the jugs to use the pumps. The resin used to glue the box in was also used to finishing a paddle that I made for my stand up board. I noticed the other day that it never really got hard on my paddle gloss coat. Sure enough, the resin under the box was still soft and sticky. Also must of had some air under the box.
My side boxes are holding firm. We will see what happens after a few hard bottom turns… Hopefully after another week maybe it will have hardened a little more. I just set the center box again. Tomorrow I will lam and hot coat.
For sure it will be in the water next week, but I got to say that I am real leary of post curing. I have left other boards out in the sun before but I was using a fast epoxy from fiberglass Hawaii and had no problems. This medium epoxy I have now takes forever to harden. I will be trying US composites fast epoxy next time. I may have found a source for RR epoxy here in Hawaii, so may try that if affordable.
It was hot, sunny, and humid when I bagged it the other day. Around 84 degrees F and 80% humidity. Id did seem quite hot on the top surface of the board, but the temp on the guage was around 125 degrees. Not sure about the accuracy. Wasn’t worried though because RR says to cure at 212F for 2 hours. I see now that others post saying some foams melt way before that temp.???
I think someone asked–I live here on the Big Island of Hawaii. Not quite the quantity or quality of Oahu surf, but I still manage to find my share of powerful juicy waves. Just got to be on it and check every day. I will work on my picture posting ability. Got a few other things to share if I can get a real photos posted.
Thanks for the replys
Aloha
Black bag on a 29C day? That sucker is gonna get HOT inside!
Yeah, I’d be worried about delams for sure.
