Soldering iron to do pre-soldering treatment
(1) Hold the electric soldering iron in the right hand. Use needle-nose pliers or tweezers with your left hand to hold components or wires. Before soldering, the electric soldering iron should be fully preheated. Tin should be eaten on the blade surface of the soldering iron head, that is, a certain amount of solder should be brought on.
(2) Place the blade of the soldering iron tip against the solder joint. The electric soldering iron is at an angle of about 60° to the horizontal plane. To facilitate the flow of molten tin from the tip of the soldering iron to the solder joint. The time the soldering iron tip stays at the solder joint is controlled within 2 to 3 seconds.
(3) Lift the tip of the soldering iron. The left hand still holds the component. The left hand can only be released after the tin at the solder joint is cooled and solidified.
(4) Rotate the lead wire with tweezers to confirm that it is not loose, and then use the pliers to cut off the excess lead wire.
Welding quality ----- When welding, it is necessary to ensure that each solder joint is firmly welded and in good contact. To ensure the quality of welding, its typical features are bright tin spots, smooth without burrs, and moderate tin content. The tin and the object to be welded are firmly fused, and there should be no false welding or false welding.
False soldering means that only a small amount of tin is welded at the solder joint, resulting in poor contact and intermittent on and off.
False welding means that it seems to be welded on the surface, but it is not actually welded. Sometimes the lead wire can be pulled out from the solder joint by pulling it out by hand.
When soldering the circuit board, be sure to control the time. If it is too long, the circuit board will be burnt, or the copper foil will fall off.
When removing components from the circuit board, stick the tip of the electric soldering iron on the solder joint, and pull out the component after the tin on the solder joint melts.
How to replace components ------ In fact, replacing components could not be simpler. It can be easily done with a solder suction device, and all the solder on the component pins will be sucked off. Here is a little trick for you. The current circuit Most of the boards are finely crafted, the solder is rarely used, and it is difficult to melt off, so it is much easier for us to add some solder to the pins and then use the solder absorber. Another method is as mentioned above, directly use the electric soldering iron to melt off the solder, but there is a lot of danger in this way, not only to be careful that the solder joints are not completely melted, but also to be afraid of burning out the components if they are in contact for too long. The common method is to use tweezers to hold the component and pull it out when the temperature is high. When the temperature reaches, the component will be pulled out, but remember not to use too much force, otherwise it will be troublesome if the pin breaks in the solder. Of course, for the sake of safety, it is better to use the two methods together, because sometimes the suction soldering is difficult to be sucked clean because the component socket is too small. Heat the soldering iron and remove it.
Welding is actually not that scary. It may be difficult for beginners to master in the first try, but it will become more proficient if you practice more.
