Why would you make a bong out of a can... that would take so much longer.Just poke holes in it and call it a pipe.
Metal is stuff.I always smoke out of a pipe, a can or a gravity bong.The aluminum is terrible to smoke out of but just don't do it alot.otherwise glass all the way.
I said use metal over aluminum if you have to.
This topic makes me wanna smoke again, but I only smoke once a week and I already smoked on Friday. :c