Gas soldering iron

In the practice of auto and motorcycle enthusiasts, one often has to deal with the need for soldering or welding. Several years ago I quite accidentally saw a gasoline soldering iron made in the GDR that was used for these purposes — and that was when the idea arose to make a similar one, but running on gas. The result exceeded all expectations — and now the gas soldering iron has a worthy place in my set of tools. Using it during repairs of body panels, radiators, and terminals of large-section copper cables confirmed the viability of the design. The main advantages over the traditional “hammer” and blowtorch are: the ability to solder continuously, maintaining a set temperature, which is important when performing a large volume of work, as well as the ability to regulate the degree of heating.

To make the soldering iron, a cork-type valve PPB-1, used in the oil line of a GAZ-53 vehicle, was needed. Its modification consisted of turning the front part down to 12 mm and cutting an M12×1.5 mm thread. A brass nozzle with a 0.8 mm diameter hole was made and pressed into the valve body. It should be noted that the holes in different valves differ by 0.1 mm in one direction or the other. Therefore, fitting the seating surface of the nozzle was done individually.

A section of stainless steel pipe with an internal diameter of 23 mm and a wall thickness of 1.5 mm served as the material for the nozzle. The blank was machined to the required dimensions on a lathe. The rear part of the nozzle was flared on the lathe as well, using a pressed bar.

A duralumin rod 20 mm in diameter and 160 mm long was used for the gas line/handle. A through hole 4 mm in diameter was drilled in it. In the absence of special tooling, this operation was performed in two steps from opposite sides. Then one end of the rod was turned to match the existing hose diameter. The textolite handle was fixed with ED-P adhesive. The threaded connection of the rod to the valve was sealed with FUM tape (sealant).

The soldering iron tip was made from a copper bar 20×20 mm in cross-section. A 9 mm diameter rod from an MTZ engine intake valve was used as the stem. The connection to the tip is an M8 threaded joint with subsequent peening. (It makes sense to make several different tip shapes at once, depending on the intended use.)

Since the working pressure of a standard (household) gas regulator is not enough for the burner to operate normally, an adjustable regulator is used. To prevent liquid gas from entering the burner passages, the cylinder is kept only in a vertical position.

It should be noted that this device is no more dangerous than an ordinary blowtorch, and when working with it one should observe general fire safety rules, including monitoring the tightness of the gas line connections.

The burner is lit with the valve barely open. The valve also regulates the flame intensity and, consequently, the degree of heating of the soldering iron tip. To ensure complete combustion of the gas-air mixture, the distance from the nozzle to the heated surface of the soldering iron should be at least 15 mm.

“Modelist-Konstruktor” No. 9’99, Yu. Shorets