Abstract: A handheld soldering tool has a fuel reservoir or tank (10), a tip (1) heated in use by a catalyst assembly (2), a valve assembly (9) for controlling flow of gaseous fuel from the reservoir (10) to the catalyst assembly (2), and a piezo-electric ignition device (7) for igniting gas released from tank (10) for combustion during an initial warm-up period to bring the catalyst to its operating temperature. A spring member (19) mounted on a rocker member (17) serving to transmit an actuating force from a switch member (18) to the piezo device (7) is arranged to momentarily interrupt the flow of gas from valve assembly (9) through Venturi (16) to combustion region (15), to terminate the initial combustion period, during reverse movement of the rocker member (17) from an ignition disposition to a non-active or gas-flow disposition.