I have a used Wenonah Spirit II in ultra-light tuf-weave that I got off of a guy for pretty cheap last year. It’s a 1995 and needs some work and with the warm weather (where I’m at) I figured I’d get to it. Major problems are that both float tanks have cracks in them near the bottom of the hull and one is definitely worse than the other. Also, apparently the previous owner had someone very large in the bow seat and snapped the rear metal cross bar on the tractor style sliding seat mount. The bar punctured a hole into the bottom of the hull and foam core, but did not come out the other side. It does not leak however there is a bump that you can feel on the underside of the hull. Lastly, on the bottom of the inside of the hull all around the foam core there are small areas where it seems the epoxy is chipped or something (last photo). Seems like you could just put more epoxy in them and let it dry but then again I’m not sure. This is my first “real” canoe, so any advice on how to fix these things would be greatly appreciated and obviously I would like to keep it as light as possible! Thanks for any insight!
Use marine epoxy and fiberglass cloth for the repair. For the flotation tanks you can make a fillet with thickener and then use fiberglass tape. The tanks may have gotten wet. They are filled with Styrofoam.
Per advice here, I used Lexel where my bulkheads were detaching. Seemed to work well and easy to apply but I haven’t filled the boat with water to see how well they work.
First off, regarding float tanks there are two different varieties, open top and sealed. There are also the float tanks in aluminum canoes where there is not a watertight seal between the “bulkhead” portion of the tank and the hull sides. On the latter type and open top tanks, the tanks need to be filled with some type of flotation material or else the tank would fill with water and provide no buoyancy. Sealed float tanks do not need any material inside them as the air provides the buoyancy. I strongly suspect the tanks in your canoe are sealed but to be sure look up under the deck plates. If the top of the tank is completely covered with fabric, it is a sealed tank.
Your canoe was most likely constructed with vinylester resin. Epoxy will work fine for a repair. I would seal around any edge of your tank where is appears the junction of the tank with the hull is failing or there is a gap. After cleaning up and loose fragments of resin and fabric I would first fill in any voids with epoxy, then apply a strip of fabric over the junction. Fiberglass tape probably would be the easiest material to work with for this purpose.
For the damage to the bottom of the hull and the bottom core I would fill in the void extending into the foam core with epoxy thickened with silica powder first. This may require several applications of epoxy as it settles into the void. First try to push in any bump on the exterior of the hull and try to splint it in place as the epoxy cures. I would then cover the area of the interior hole with a patch of fiberglass that extends at least 2" past all edges of the hole onto intact, undamaged hull.
I can’t be sure exactly what is going on along the edges of your bottom core from just the one photo. It could be that you just have some defects in the surface layer of fabric resulting in small resin voids that occurred during lay-up of the hull. But the edges of a foam core represent a stress riser where the thicker, stiffer hull bottom meets the thinner, more flexible hull sides. It is an area where cracks can often occur in the thinner hull right along the sides of the core. Try pushing in on these areas from the outside of the hull to see if there is any unnatural give. The light colored lines visible in your photo might indicate areas where the fibers of the structural fabric have disassociated from the resin matrix weakening the hull.
If the hull feels strong in these areas I would again just remove any loose edges of resin and fabric, clean up the area, and fill in the defects with epoxy. If it seems there is some degree of damage to the hull itself I would again apply a strip of fabric over the junction of the foam core and the hull side.