There are products available to weld aluminum using a propane torch. I've fabricated two hanging canoe saddles using it and have been very happy. Propane torches are cheap and the welds seem very strong. I bought the stuff I used on Ebay, it is called Dura Fix aluminum welding rod.
While I really like epoxies, welding aluminum gives a much stronger bond.
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13