1.solder bar 2.lead free solder bars 3.used manual soldering ,wave soldering optional 4.8%Zn 3%Bi 5. ... used in electronics, plumbing, and assembly of sheet metal parts. Manual soldering uses a soldering iron or soldering gun. Alloys that ... 'hard soldering', 'silver soldering', or brazing.Lead-free solders in commercial use may contain tin, copper, silver, bismuth, indium, zinc, antimony ...