Watch this video to learn how to make a SoBe bottle gravity bong. You will need a SoBe bottle & cap, a knife, a phillips head screwdriver, and a wrench socket (of whatever size). Plain paper is used for making smoke. Obviously, you shouldn't smoke paper. Steel is recommended for the screen. Copper ionizes easily, and it's oxidation remnants are unhealthy for consumption. But depending on what you burn the copper is immediately coated with a resin skin, leaving you perfectly safe. Copper's melting point (1984.32 °F) is nowhere near the auto ignition temp of butane (~760 °F). However, I recommend using 24 gauge wire or above if making a copper screen.