I have tried it, or a simular type of aluminum solder a number of years ago. It didn't pan out worth a toot for me. I did get to talk to the vendor a couple of weeks later at another fair he was selling at. He let me try it at his booth and I had pretty much the same results. Then he showed where I was going wrong. The first and most important the area has to be clean. Very clean. The heat has to be just right, it's easy to be to cold on heavy stuff and to hot on the light stuff. Heat the area, not the filler stick. And you apply it to the area by rubbing it on,(seems to 'tin' the area) and not trying to weld it in like you would with a steel rod. I haven't done it yet, but I think putting aluminum end tanks on a aluminum rad might work out not to bad with this stuff. The alloy in the rod is supposed to be better now than in the past, I haven't bought any for along time, so I can say for sure. But I plan on giving it another go. Sniper