Fiberglass weave showing through epoxy

�I fibwrglassed the outside of my shearwater kayak, and after I put on the third coat of epoxy I noticed little bits of the fiberglass have started showing. Not raised like the weave hasn't been filled, but almost like in some places the fiberglass has separated itself from some of the epoxy. I live in Alabama where it's hot and humid all the time. Could this be the problem? Should I be concerned? It's annoying that it's showing, but it's the under side of the hull, so it's not the end of the world so long as it doesn't worsen. Thanks for any help.

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RE: Fiberglass weave showing through epoxy

Can you share photos? It's a little difficult to picture exactly what you're dealing with. FWIW, in certain light I can see the weave on some of my boats, too, but don't think it's a seperation issue. In any case, I've been paddling one of them for about 10 years under all sorts of conditions and so far, it still floats!

RE: Fiberglass weave showing through epoxy

   It might be that the fiberglass floated or didn't adhere to the wood in spots and what you are seeing is the fiberglass weave on the bottom side, between the epoxy and the wood. Sort of like a little bubble between the wood and the glass.

I had a few spot like that on the inside of my PMD where the glas transitioned from the bottom panel up onto the first strake and I didn't make a smooth enough transition fillet.

I could tell they were bubbles because I could push on them and they would flex a little bit.

I didn't know if it would matter that much, but just in case, I drilled a few tiny holes in each bubble and used a glue syringe to inject epoxy into each bubble. Looked pretty rough for varnish, but I'me going to paint over that section so it doesn't really matter.

RE: Fiberglass weave showing through epoxy

   Sorry, I didn't get a picture initially, then got to worrying about what I saw, so I posted on here before I got a photo. But here's a photo of what I'm talking about. Again, it may be nothing, but wanted to make sure before glassing the top which will be seen more.

RE: Fiberglass weave showing through epoxy

   The checked weave looks like a partially starved initial wetout, but the cloudy areas look like contamination under one of the coats -wood glue looks like that on raw wood, but since you report noticing it with later coats it's likely to be blush. Warm humid areas cause even so called "non-blushing" epoxies to blush. If it bothers you, use an abrasive pad and water to clean the outer layer of blush, then wetsand through the outer epoxy layer.

Get in the habit of that water/scotchbrite routine after every epoxy operation. 

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