Why is the solder wire on the electric soldering iron not sticky?
Introduction and working principle of electric soldering iron
The electric soldering iron is mainly composed of a handle, a power cord, a heating core, a soldering iron head, and a mica sheet (some precision ones also have various temperature control circuits). According to their heating methods, they can be divided into two types: internal heating electric soldering iron and external heating electric soldering iron Classes, which correspond to different use cases. The reason why it is called an internal heating type electric soldering iron is because the soldering iron head of the internal heating type electric soldering iron is hollow, and its heating core is in the inner hollow of the soldering iron head, so it is called an internal heating type electric soldering iron.
Internal heating type electric soldering iron tip, the last hollow structure
The external heating type soldering iron tip is just the opposite of the internal heating type soldering iron. The tip of the external heating type soldering iron is solid and generally made of copper. The heating core of the external heating soldering iron directly wraps the soldering iron tip, that is, the soldering iron tip is inserted inside the heating core, so it is also called an external heating soldering iron.
Externally heated soldering iron tip, solid construction
Whether it is an internal heat soldering iron or an external heat soldering iron, their working principle is the same. The power plug of the electric soldering iron introduces household AC220V alternating current to both ends of the heating core, and the heating core is energized to generate heat.
A small part of the heat emitted by the heating core is lost to the surrounding air, and most of the heat is exported to the soldering iron tip. The temperature of the soldering iron tip can reach 200-450 degrees, which can melt the solder for welding.
Why doesn't the soldering iron stick to the solder?
1. The electric soldering iron has been used for a long time, the internal heating core is aging or damaged, and the heat emitted cannot reach the melting point of the solder, resulting in the soldering iron tip not sticking to the solder.
2. During daily use, the soldering iron tip is not tinned after using the soldering iron, which causes the soldering iron tip to oxidize with the air at high temperature.
Oxidized black soldering iron tip
3. After using the soldering iron, it was not cut off in time. The soldering iron is in a high temperature state for a long time, and it will oxidize with the air, resulting in non-stick solder.
4. In order to pursue convenience in daily soldering, acidic flux is used, which oxidizes the tip of the soldering iron at high temperature.
5. The problem of the soldering iron tip itself. Some soldering iron tips with poor materials are used. For example, some soldering iron tips are directly made of iron. This type of soldering iron tip itself is extremely prone to oxidation.
How to solve the problem that the soldering iron tip does not stick to the solder
1. Prepare high-quality solder, rosin, and high-temperature sponge. Turn on the electric soldering iron, when the temperature is high, insert the soldering iron tip into the rosin, and shake it back and forth. Then take out the prepared solder and melt it in contact with the tip of the soldering iron.
2. If the soldering iron tip has been oxidized and blackened, you can prepare a file (if there is no file, you can also prepare sandpaper). Use a file or sandpaper to polish the soldering iron tip to remove the black oxide layer on the surface of the soldering iron tip.
file
3. The tip of the soldering iron is generally made of metallic copper. After oxidation, black copper oxide (CuO) will form on the surface. Copper oxide is non-stick solder. You can insert the tip of the soldering iron into a 90% alcohol solution for treatment. It should be noted that it should be put in the unheated state, then energized, and taken out after 1-2 minutes, the problem of oxidized non-stick solder can be solved.
After talking about the solution to oxidized non-stick solder, in order to avoid this kind of oxidation in the future, how should we use the electric soldering iron correctly?
1. The first point to talk about is the use of this flux (soldering paste). Most of the fluxes are acidic fluxes, which have a certain oxidation effect on the tip of the soldering iron. Try not to use them.
Here I recommend a more useful method for making flux, that is to grind rosin into powder and pour it into alcohol solution for full dissolution. This ratio is generally 40% rosin powder plus 60% alcohol solution, and there is no problem with a little more rosin. It should be noted that medical alcohol cannot be used, and an alcohol solution of more than 90% should be used, and the container should be kept sealed.
2. The second point is the power outage problem. Many friends are not used to unplug the power plug in time after use. When the soldering iron tip is in a heated state, it will naturally oxidize the non-stick solder. Therefore, daily use needs to be done, and the power supply should be cut off in time after use.
3. The third point is the tinning of the soldering iron tip that many people ignore. In order to save trouble, most of the soldering irons will not tinn the soldering iron tip after using it. Even after the tip of the soldering iron is powered off, its temperature is very high, and it will oxidize with the air, and tinning it before power off can prevent it from being oxidized.
4. The fourth point is about soldering tin. There are good soldering tins and bad soldering tins. In order to save money, most people buy cheap solder wire. Although it is cheap, the quality is very worrying. Solder slag is easy to appear, and even becomes solder slag when heated.
5. The fifth point and the last point I want to emphasize is the soldering iron tip. A good soldering iron tip can achieve twice the result with half the effort. For our daily use, we can use a round tip or a knife tip, but we need to buy a better soldering iron tip. For example, the soldering iron tip made of copper is very durable and has strong oxidation resistance.
