Abstract: Methods and apparatus for applying molten solder are disclosed. A system for applying solder to a workpiece includes a conveyor for moving a first workpiece along a machine direction, and a first selective soldering nozzle to apply solder to the first workpiece while the first workpiece is moving along the machine direction. The system can also include a flux application area to apply flux to bottoms of workpieces, a heating area to heat the bottoms of the workpieces, and a conveyor to convey the workpieces. The workpiece can constantly move through multiple areas, such as a flux application area, a heating area, and a selective soldering area. As such, two or more areas can operate on the workpiece simultaneously and while the workpiece is moving. The method includes applying solder from the first selective soldering nozzle to the first workpiece while the first workpiece is moving along the machine direction.