: 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--

Hi Bruce

I believe the problem lies in the Red Zones above.

First, you started coating the plywood mid-day and the temps. probably increased during the remainder of the afternoon. This most likely caused some out-gassing of warm air in the wood.
That in itself is not the entire problem. Had you let the first coat of epoxy get to the green ( non-tacky ) stage it probably would have been easy to sand any little bubbles that may have crept into the resin.
The main reason was putting the glass and another coat of epoxy over the first while it was uncured, allowing any escaping air to be trapped under the glass.'

I'm guessing, but after the glass went on you probably relaxed and left the project for a few hours..?? Had you been on the spot when the bubbles started you may have been able to squeegie them out or fill them while wet. Hard to say.

Best case scenerio would have been to start your epoxing when the temps first start to drop in the evenings. That way the temps decreasing would have drawn epoxy INTO the wood and sealed it while curing. Wait till the green stage on the sealer coat and then lay the cloth over and saturate it.

I don't know for sure on the patchwork, but I would cut that glass off and do the patch. My reasoning would be that where the cloth is turned up and epoxy is hardened, the glass cloth will not lay down along that line. When you go back and sand, you will be cutting off those edges and exposing the end fibers to the surface of the epxoy. I don't know for sure but I've heard you will see shiny spots where those fibers are. ??

I would feather and patch the area. You may get a little color difference in those spots... ?? I guess it's possibly a " Six of One / Half-Dozen of the Other " situation.

Either way I don't believe you will have a strength issue. Just appearance... and possibly only to the "knowing " eye.

Hope you get back on track soon and not worry about this little mishap..
It's not a big deal.. and will probably figure very small by the time you are done with the boat.

Rehd