I have never welded, but soldered a lot. So when I needed to connect some square aluminum tubing I figured this might work. First you have to make it hot! Use something like card gas. Surfaces must be clean. After about 4 hours of fumbling for about 10 joints I gave up. Only about 2 or 3 of my joints held. The rest fell apart. I don't know if it was because the aluminum surface wasn't clean enough. What I can say is that the joints that held up were great. Stronger than aluminum itself. I tested these good joints with a hammer and the aluminum broke before the joint. Maybe it was my inexperience, maybe it was something else. But it just didn't work for me. I ended up re-cutting all my parts and screwing them together.