I just bought a used Dagger Atlantis sea kayak. I took it out for an hour paddle and it performed fine. Examining the hull there is a defect on the apex of the hull in the bow (its in the portion of the hull were there is a fairly defined ridge, 5" north of the bow hatch). The defect is a 2x2 mm hole(guessing a bubble). It did not leak and the defect is indetectable inside the hull. I am assuming the hull is 4mm thick or more along this ridge but wanted to get some input as I am headed out on an overnight trip shortly.
repairing polyethylene As far as I know, all Dagger Atlantis kayaks were molded from super linear polyethylene (Dagger calls it EXL).
Linear polyethylene has been most commonly repaired with thermal welding, and it may be possible to melt material from a polyethylene welding rod and put it into the defect.
Here is a pdf file describing repair of linear poly boats:
I have done some pretty extensive repairs of polyethylene boats (both solid and 3-layer, foam core poly) using West Systems G Flex epoxy but for a successful repair it is absolutely necessary to “flame oxidize” the surface of the poly to polarize it before applying the epoxy. This is easily done with an inexpensive propane hand-held torch, but the bonding surface must be accessible to the blue inner cone of the torch’s flame. If so, you can drip mixed G Flex epoxy into the defect and it will bond.
Few adhesives have bonded successfully to polyethylene because of its very non-polar nature.
If you could put up a photo of the area of damage it would be helpful.