Metal Bonding Questions
I ran across Sealfast when I worked for an aircraft repair company. We were putting entire wing structures together with this stuff.
I've used it to seal holes in floor pans and to attach hood skins to the structural pieces underneath to keep them from drumming. Works great. Comes in cartridges and cans. Available directly from the manufacturer. I have no idea what the stuff runs these days since I have long since left the aircraft repair and maintenance biz.