: I've already faired it to 60 grit
: w/ a board. The keel is actually 2 thin pieces glued at the center; and
: the split seems to be at the glue line. I'm guessing that this is from
: shrinkage of the strips all along the hull. In fact, I have a couple of
: other strips on the hull that are doing the same thing.

: My questions: Is this from shrinkage? If so, will it keep happening? . . .

Probably shrinkage is a good guess. Winter air is dryer, and when it is heated the humidity drops even more. Moisture evaporating from your wood in a winter environment can certainly shrink and crack.

Not to worry, though. This could actually be a good thing. When you apply your epoxy resin it will soak into those cracks an crevices, gluing everything solidly, and sealing the wood to keep out later moisture.

: Should I
: expect to go into my shop one night and find splits and cracks all along
: my once beautiful hull? Do you think this happened because I didn't use
: enough glue on those joints? Too much glue?

I doubt the amount of glue had anything to do with it.

: Finally, what do I do about them? I tried squeezing the hull, but the forms
: prevent the cracks form closing. Will they close up with a change in
: humidity? Will I have time later to try to close them up?

Well, added humidity would make the wood swell, but you don't want to have damp wood sealed under epoxy. If you had that, and then left the boat in a sunny spot on a hot day the trapped moisture would try to evaporate, and the area between your two layers of fiberglass would turn into a long, narrow pressure cooker, filled with steam under pressure, and trying to escape. That would lead to delaminated areas and trapped "bubbles" under the glass.

Before the wood is sealed with the epoxy you want it as dry as possible -- and it looks as though you are going to get this. Don't worry about the tiny cracks. The resin fills them and they look like the natural lines of wood grain.

Sounds like you are ready to go with a finer sand paper for a couple of hours and then you'll be ready for the glassing in almost no time. After that point things will look much better.

hope this helps

PGJ