: I filleted and taped the interiors of the hull and deck this past weekend.
: Looked OK. But like a kid who can't stop painting a picture when the
: picture's done, I got ambitious and decided to also add a layer of 4 oz.
: glass over it all. Now it doesn't look so OK. :-(

: First of all, the glass retained lots of long threads at the edges, no matter
: how carefully I cut the cloth. After epoxying, some of those threads are
: needle-sharp spikes. Yes, I punctured my finger on one. I think the only
: thing to do about those is trim them as best I can, then sand the edges
: down. If anybody has a better idea, please post a reply with description
: of what to do. I intend to remove those bleeping spikes Wednesday, before
: they inflict any further injury.

You can sand those spikey things off with no problem at all. Once done, if you want a clear finish, apply a light coat of epoxy and use a squeegee to wipe off excess or a piece of foam roller mor foam brush. I've punched through my fingertips many times. Very painful, for sure!

: Second, there are lumps in many places. I have been shaving some of them down
: with a scraper and will probably leave them alone other than that, as long
: as they contain epoxy and not air. Some of the lumps formed from
: "fur" shed by the cloth as I spread the epoxy or squeegeed. I
: did wipe off these clots if I could, but in some cases the clot contained
: a long thread that, when pulled, began to unravel the cloth at an edge!
: Eeeew. So I left those clots in place and figured I'd shave/sand them down
: after they dried. Actually, it's gonna be SAND with a Dremel tool, because
: by tomorrow the epoxy will be pretty hard.

The lumps can be sanded off if-and-only-if they are not under the weave of the glass. Sand carefully so as not to damage the weave or you will have to patch the glass. If they are under the glass and you want them gone, sand through the glass and patch with at least 3 inches of overlap for the patch. I have used the dremmel for that very reason myself. It always seems that I miss a clot and find it only after the epoxy has hardened. Murphy's Law is a pain sometimes.

: Last but most important, I do have some bubbles. Not just the teeny ones that
: came from too-vigorously-mixed epoxy (a lot of those closed up before
: drying anyway). I have some larger bubbles here and there also. While the
: epoxy was wet, I took pains to press down on any seams/joints with the tip
: of the paintbrush or the edge of the squeegee, so I managed to remove any
: large bubbles from the joints that way. But there are bubbles in other
: areas. Do these bubbles pose a structural problem? I presealed the wood
: before putting any glass down, so there is no raw wood directly under the
: bubbles. (I tried to squeegee those bubbles out, but usually that would
: move the cloth, resulting in more bubbles elsewhere!)

Any large bubbles will affect the structural integrity of your work, depending on where they are. The point of a good layout is to create direct contact with the glass on wood using epoxy as the contact medium. If there are bubble present then there is no structural integrity in that spot. Seams must stay bubble free or they will be weak. Any large bubbles are a piece of cake to fix. My technique was to drill very small holes at each end of the bubble. I then took a syringe of epoxy and injected the glue into one hole until it erupted through the other hole. I kept up the injection pressure until all air was gone. Wiped it to keep it neat. I had to do this when I laid out the Kevlar in my cockpit. The bubble were bigger than a quarter but filled nicely using the drill/syringe technique.

: Lastly, will glassing the exteriors be easier? The interior was a pain, but
: I'm thinking the convex outer surface will be easier to do a neat job on.
: At least excess epoxy can be squeegeed DOWN and right off the edges.

The exterior is a lot easier. Be careful not to starve the glass of epoxy by wiping with too much pressure. You should be able to see the weave while you wipe but don't wipe with enough pressure to move the glass, that's when you begin starving the glass.

I hope this helps. What are you building?

Robert N Pruden