Abstract: An improved soldering device is provided, one that is structured for the reception of and use with a new cartridge that is a self-contained supply of solder. When the cartridge is inserted within the soldering device, an operator, using only one hand, is able to advance the solder from out of the cartridge and to a location in close proximity with the soldering tip of the device. With that same single hand, the operator can energize the heating element to supply heat to the soldering tip. The advancing and energizing structure permits the device to remain energized throughout the advancing operation or, optionally, to smoothly effect an intermittent energization and deenergization of the heating element to reduce the total quantity of heat supplied to the soldering tip even while the solder is being advanced.