Flexible epoxy

Two-part Urethane Adhesive

This is as close to "bomb-proof" as I have found a glue to be. It seems to stick to just about anything, although 3M says it's for metals and plastics. I have used it for gluing D-rings - and other things - into my whitewater canoes. The rings have been able to hold me boiling through big rapids, often upside-down. For this application the glue joint needs to be flexible and waterproof...and this stuff hasn't ever failed me. How it is different from epoxy: Fills gaps. Flexes under stress without giving away. Sticks to smooth plastics like PVC or vinyl. Seems a LOT stronger than epoxies. You'll have to find this in a specialty store or order it over the web.
-- Fen Sartorius

3M Scotch-Weld 3532 B/A Urethane Adhesive
$15/ 2 0z. tube kit (6 per case)
Available from
http://tinyurl.com/cyzzr

via Kevin Kelly http://www.kk.org