PURPOSE: To obtain a carrierless soldering device which automates regulation of the hold width of a substrate, supply, conveyance, and recovery, by providing an automatic substrate supplying device, solding device, and automatic substrate recoverying device each provided with special mechanism, respectively.

CONSTITUTION: An automatic substrate supplying device A lowers a magazine rack 2 held while its width is adjusted to a substrate K by a lowering machine 3, and the substrate K is sent out by a cylinder 1. A soldering device B is provided with a spray type fluxerI, hot blast preheater II, preheater III, dip type solder vessel IV, and cooling fan V successively, and the substrate K is conveyed by a conveyor 28 and soldered automatically. Then, return parts are provided on both end parts of this body B, and a curvature preventing device such as a wetting part and an impeller and interval adjusting mechanism for a holder are provided near the solder vessel IV, performing excellent soldering. The automatic substrate recovery device C mounts the magazine rack 2 on a lifting machine to lift the rack.