Abstract: An apparatus for depositing a selected pattern of solder onto a substrate on which electronic components are to be mounted. The apparatus includes a substrate support, a replaceable solder cartridge, and a solder ejector. The replaceable solder cartridge defines a cavity for containing solder and has an orifice for ejecting a continuous stream of molten solder. The solder ejector has a mechanism for retaining the replaceable solder cartridge during solder deposition and is positioned relative to the substrate support to deposit molten solder ejected from the orifice of the replaceable solder cartridge onto the substrate.