Soldering Iron

A soldering iron is a hand tool used in soldering that supplies heat to melt solder so it can flow into the joint between two workpieces. The tool consists of a heated metal tip, called a bit, attached to an insulated handle, with heating in modern tools usually produced by an electric current passing through a resistive heating element. Before electrical versions existed, soldering irons were simply large copper blocks mounted on iron rods with wooden handles, requiring constant reheating over a fire or a charcoal brazier. The first electric soldering iron, developed in the 1880s, had a lightweight platinum tip heated by electric current, and by 1889 designs had evolved to use resistance wire wrapped around the copper head; in 1894 the American Electrical Heater Company began mass producing electric soldering irons in Detroit. Later innovations include Carl E. Weller's 1946 patent for an instantaneous heating soldering gun and his 1960 Magnastat model, which used temperature sensitive magnetic tips for automatic temperature control. Solder melts at around 185 degrees Celsius, while soldering irons are designed to reach a temperature range of about 200 to 480 degrees Celsius, and the tool is used mainly in electronics assembly, installation and repair, though high volume manufacturing uses other soldering methods.