fusioneng wrote:
Just FYI from my perspective (I'm a plastics engineer), I have had dismal luck trying to use any types of epoxies or foreign adhesives (foreign meaning any other material (ie... Urethane, epoxy, etc). It seems nothing sticks to the cross linked polyethylene well at all except via melting to itself that I have found anyway.
I have had good success fixing cracks in basically flat areas of a kayak by drilling holes at each end of the crack, and then gluing raft repair fabric over the crack with vinyl glue. Contact cement doesn't work; it will quickly separate from the kayak. My repair trip for multi-day whitewater kayak trips includes pieces of raft repair fabric and vinyl glue, and I've used this successfully several times. However, the crack in Duncan49's kayak couldn't be fixed with this method because it dives down into the seat holes.
Here are pictures of us repairing a whitewater kayak which developed a crack on a four-day whitewater kayak trip on the Jarbidge and Bruneau Rivers in south central Idaho. For extra strength you can glue patches on both the inside and the outside of the hull. I cover the patch on the outside of the hull with duct tape to protect it from being scraped off by rocks.

