Soldering with hand irons, or hand coppers, or soldering coppers, is the traditional way to solder that's been done for generations. The hand irons are heated up in a "solder pot" and the copper (or other metal) components of a roof (or other application) are soldered with bar solder. In this video a builtin 20ounce copper gutter on the Warren County (PA) courthouse is being installed by The Durable Slate Company of Columbus, Ohio. The hand irons are cleaned during use by quickly dipping the hot irons into a jar of 50% water and 50% Ruby Fluid flux. Here the solder is pure tin, a lead free substitute for the typical 50:50 tin/lead bar solder. Filmed by Joseph Jenkins, author of the Slate Roof Bible, 3rd edition (https://www.slateroofwarehouse.com/Sl.... More about soldering products can be found here: https://www.slateroofwarehouse.com/so....