Hope you don't mind, I'm going to post about my canoe... but it's really an "open" kayak since it has a low seat and is designed to be paddled with a double paddle ... yeah.. that's it.....

Well, I fiberglassed the outside of my Wee Lassie Saturday... I ended up with bubbles forming on Monday evening (or that's when I saw them). Several bubbles, concentrated in the same general area (an area of about 2-3square feet) and they are varying in size but averaging 1.5-2in long and 1/8" to 1/2" wide. Funny thing is, the epoxy is cured (I assume) but these bubbles are soft and they 'almost' wet out again when I push down with my finger on them.
I 'think' I know where I went wrong, but I thought I would ask the opinion of those here..
I used the USComposites thin epoxy (2:1) and did the coating of the wood around noonish Saturday, the temp in the garage was 79 degrees. I waited 2 hrs or so and then went to put the fiberglass on. This being my first boat, I guess I didn't know what 'tacky' means, because the epoxy was still somewhat wet..., enough so some of the fiberglass wet-out itself. I proceeded to wet out the 4oz glass, really without incident (or so I thought). Let that coat dry for 4 hrs or so and put on a fill coat (again.. I think in retrospect it was not cured enough). Sunday noon-ish I put on another fill coat. Everything is looking dandy at this point... at least to me... until I go Monday and the boat is sitting in the garage and I notice a pattern of the above described bubbles forming.

Some theories... 1) as mentioned above I put the varying coats on way too soon. 2) the pattern of bubbles 'happened' to correspond to the part of the boat that was exposed to the sun through the garage window for a part of the day (grasping at straws here). 3) I 'think' that area of the boat also got a somewhat thicker application of epoxy on the fill coats. 4) I'm not 'positive' I mixed the epoxy well on all the coats. I remember thinking as I was about to put on one of the fill coats "Gee I didn't mix that enough... I wonder if I mixed the other batches well enough".

OK, now on to the "what do I do about it". 1) The bubbles are all such that I could cut the fiberglass into a "flap" (remember the fiberglass that makes up these bubbles is still pliable) put some epoxy down, maybe poke some holes in the "flap", wet the hole thing out and be done.. I don't know if this is advisable... probably not, because it seems too easy. 2) Cut out the bubbles completely, feather the edges, put in a patch.. etc. or 3) something I haven’t thought of..

D@ng, this learning curve is fun! --sarcastic grin--