... assembly of sheet metal parts. Manual soldering uses a soldering iron or soldering gun. Alloys that ... 'silver soldering', or brazing.Lead-free solders in commercial use may contain tin, copper, silver, bismuth, indium, ... a tube, with a brush, from the core of the solder or in any combination, depending on your personal ... your application, but to be safe, always use a flux core so that you don’t forget. ...