as long as its sealed with epoxy so it does not absorb water....it's fine.

sealing has to be the hole in the hull for the toggles as well as the wood inside the hull.

h

   I might suggest some other wood that does not absorb water as easily.  If you don't get it perfectly sealed, or damage the area, balsa will act like a sponge.  If you go the end pour route, use microballoons.

I carved a piece of pine 2x4 for the end so I would have something solid to screw a padeye to if I wanted to attach a tie down rope or painter.   Pine or cedar would be stronger than balsa.

   Flocho said,  "............... isn't needed there for its structural strength,........."

.

I don't think I'd say the "stem" of the boat has no structural importance.  It ties the keel to the gunwales. The end pour forms this stem component. Most wood boats would have an appropraiate shapped wood member. The early epoxy saturation boats were sometimes made of balsa. Any wood will rot if water penetrates the shell. Cedar would have some natural resistance and be sturdier.

Thanks for the replies! I had not considered the possibility of needing something more substantial than balsa for adding a pad eye, etc. It also makes sense to me that the stem may need to be a little more "beefy" than what balsa would provide. I am currently trying to source a few planks of WR cedar locally, so if I have any luck with that, maybe there will be enough to fill the stem. Thanks!  

i thought i would throw a couple comments about my experience with end-pours that may be useful.

first, for the kayaks. in my experience, there are a couple reasons for the end-pour and fwiw....there are alternatives to address each concern absent an end-pour.

first reason - you want to drill a hole in the ends for toggles and you don't want water getting into the boat through the holes.  so the endpour creates a solid through which you can drill the hole.  in this case, the end-pour need only be big enough do the hole goes through the end pour.  i do this routinely, and to keep it light, i use an epoxy/microballoon mixture held in place be a small temporary dam whose location is based in a line i draw that is 1/4 inch back from where i expect the wall of the hole that will be drilled will be.  all that said, some folks dispense with an end-pour for this and glue a tube in place to create the wall for their toggle hole.

second reason, to have a place to secure the ends of the deck hull. on a taped hull...it is almost impossible to get tape all the way to the ends.  even boats with sheer clamps don't typically run the clamp all the way into the end.   i happen to do it for this reason as well....but the end-pour for this can be quite small and i prefer to create it while the hull is exposed so that i can execute it no larger than it needs to be.  as an alternative,, on a sheer clamp boat you can simply run the clamps to the end or on a taped seam boat, just leave it out.

third reason, to have a place strong enough to for a fitting to go the end like a carrying handle or an eye strap.   i use toggle holes in kayaks and don't put handles or eyestraps in the ends of a kayak (might take another view on some other kind of boat).  but if i knew i wanted to do that, i would set it up in advance of putting the deck i wouldn't do it with an end-pour.  

fourth reason - strength.   frankly, i am dubious of this in all but the most extreme of conditions.   in all of my boats, before the deck goes on, the bow and stern internal surface is filleted, taped or glassed and properly sealed.   frankly, that this point, that is a very strong combination.

to the extent that i am doing an endpour, i do mine while the deck and hull are seperated to control the process and ensure the material is where i want it to be and i use no more material than what is needed for the process.  i would apply the same principles if i was using a carved block of pine or my micro-balloon approach.  my general sense is that most folks put way too much material into an end-pour than is actually called for and that just makes for a heavier boat.

hope this was helpful.

h 

Very good and helpful info, hspira, thanks! The shearwater sport uses shear clamps that run all the way to the stem, and at this point, I'm just getting the deck stripped. I'll have the opportunity to do the "end pour" or some alternative before permanently attaching the deck, which I intend to do. The more I consider all the possibilities, the more I like your idea of just building a temporary dam, and creating an end pour of the appropriate size. I'm pretty sure that is the method I will go with. Just have to order microballoons to keep the weight down. What do you use to build your "dams"?

thanks,

Stan

i carve/cut the dam from a spare piece of okoume scrap.

i then cover the dam piece with duct tape (epoxy wont stick to it).

i then wedge the dam in place and tape behind it (with duct tape) to ensure it won't move and won't leak.

i try to get the  micro-balloon material to be mayonaise consistency or a bit thicker (somewhere between mayonaise and peanut butter).

hope that helps

h

It does help, and again, thanks!