The soldering iron – everything to do with soldering 

The soldering iron, along with the multimeter, is one of the most important pieces of equipment in soldering accessories. A permanent mechanical and electrical connection between the component and the printed circuit board/circuit board can be created by soldering. For hand soldering in the hobby area, these are usually either breadboard or strip grid boards. A circuit concept can be quickly implemented and tested on this. The advantage over breadboard structures is that soldering creates a stable connection with low contact resistance. 

What other equipment you can use for soldering in addition to soldering iron and solder, my most important tips for good hand soldering as well as additional basic knowledge about soldering, you can find all of this on this page. 

My 6 tips for a successful solder joint 

The following description applies to soldered connections between components and printed circuit boards/circuit boards. In principle, however, the same rules apply to soldering cable or wire ends. The video that goes with my 6 soldering tips can be found below. 

Wet soldering tip 

In order to create a good solder joint, it is important to keep the soldering tip of the piston clean and to always wet it with some solder. It is best to wipe off the hot tip on the damp sponge or soldering wool before soldering and then apply some solder to the tip. This is called “tinning the tip”. 

Good ventilation 

Especially when using lead-containing solder, it is important not to inhale the resulting vapors. Professional soldering stations have an air extraction system for this purpose, a table fan or an open window with a draft can also help at the private workbench. 

Correct temperature 

To properly melt the solder, the right temperature is critical. Lead-containing solder melts at around 190 ° C, lead-free solder at around 230 ° C. If you have a controllable soldering station, a temperature of 350 ° C is usually a good setting. 

Fix the component 

The component to be soldered should be mechanically fixed on the circuit board as well as possible. In the case of THT (Through Hole Technology) components, the component can e.g., B. be inserted through the solder eye and then the wire is bent so that the part cannot slip. With SMT (Surface Mounted Technology) components you can z. B. Press down with tweezers. 

Heat & solder part 

The most important point in the actual soldering process is: Heat the component/workpiece, not the solder. Bring as much area of   the hot soldering tip as possible to the component. Only feed in the tin (with flux core) when the component and the soldering point on the circuit board are already hot from the soldering iron. The solder should be added gently for 1 to 3 seconds (not too much, not too little). The rule is as much heat as necessary, in as short a time as possible. 

Let cool down 

When the hot solder fills the soldering point sufficiently, hold the component still and remove the soldering tip. Then the solder joint can harden. The component should not receive any vibrations or movements during the phase. 

More useful knowledge about soldering 

Characteristic properties of soldering 

The technique of soldering (soft soldering) is used in electronics to connect components mechanically, electrically and thermally with the printed circuit board/circuit board or wires or cables with one another. Temperatures of soldering irons for soft soldering are in the range of 200 ° C… 450 ° C. Lead-free solder melts at around 230 ° C. Solderable metals are copper, nickel, steels or precious metals. Special solders or fluxes are required for aluminum or stainless steel. 

What is the difference between soldering and welding? 

In addition to soldering, there is another technique for joining metals: welding. Welding takes place at significantly higher temperatures than soldering, a welding flame has a temperature of almost 3000 ° C. The metals to be connected during welding are also liquefied at the connection point. When soldering, only the surface of the materials to be connected is heated; the connection is made by the solder. A welded connection is therefore much more stable than a soldered connection. 

Soft soldering vs. hard soldering 

When we speak of “soldering” in electrical engineering or electronics, then soft soldering is actually always meant. Brazing, on the other hand, is used more in craft (plumbing/gas installations) or industrial plant construction. The temperatures for brazing are above 450 ° C and you need more equipment than for soft soldering, e.g., B. Fireproof clothing and darkened safety glasses.