Re: Canoe sealer
Using a canvas covered wood canoe I can tell you that Duct tape is your emergency on the water friend.
Fiber Glass can be built up w/ fiber glass mat in the deeper spots and then covered w/ fiber glass cloth layers for a uniform surface.
After sanding if you have any small imperfections don't grab bondo; visit an auto body supply shop for a tube of 3M spot and glazing putty and apply it in thin layers. I used it to 'fill' bad spots in the canvas filler when I re-did my Old Town in 2001. The stuff adheres well, sands real smooth and is still holding fast today. I paid $12 - $14 a tube in 2001.
4th Generation @ Kamp.
3D - There are STILL a few deer left! You need to pry them out of the developments!