Soldering iron soldering tips and steps
(1) pre-soldering steps
Before welding, the component pins or circuit boards should be welded parts of the processing, generally "scrape", "plating", "test" three steps:
"Scratch": is to do a good job before welding welding parts of the clean work. The tools generally used are small knife and fine sandpaper, integrated circuits, pins, printed circuit boards to clean up, remove the dirt on it, clean up after the general need to remove the components to be coated with flux.
"Plating": is to scrape the net component parts on the tin. Specific practice is dipped in rosin alcohol solution coated in the scraping of the components of the welding parts, and then the hot soldering iron with tin head pressed on it, and turn the components, so that it is uniformly plated with a very thin layer of tin.
"Measurement": that is, the use of a multimeter to detect all the tin-plated components whether the quality is reliable, if there is unreliable quality or has been damaged components, should be replaced by the same specification components.
(2) Soldering steps
After doing a good pre-soldering treatment, you can carry out formal welding.
Different welding objects, the soldering iron working temperature is different. Judge the temperature of the soldering iron head, the soldering iron touch rosin, if there is a "squeak" sound, that the temperature is appropriate; if there is no sound, only to make the rosin barely melted, then the temperature is too low; if the head of the soldering iron touched the rosin on the large amount of smoke, it is too high temperature.
Generally speaking, there are three main steps of welding:
(1) the soldering iron head first melted a small amount of solder and rosin, the soldering iron head and solder wire at the same time to the welding point.
(2) in the soldering iron head on the flux has not yet evaporated, the soldering iron head and the solder wire at the same time touch the soldering point, began to melt the solder.
(3) When the solder moistened the entire soldering point, remove the soldering iron tip and solder wire at the same time.
Soldering process is generally 2 ~ 3s is appropriate. When soldering integrated circuits, the amount of solder and flux should be strictly controlled. In order to avoid damage to integrated circuits due to poor insulation of the soldering iron or internal heaters on the shell induced voltage, the practical application of the soldering iron is often used to unplug the power supply while hot welding method.
Soldering iron welding and its prevention and control methods
Welding, should ensure that each soldering point welded firmly, good contact, tin point should be bright, smooth and burr-free, tin amount moderate. Tin and the soldered material fused firmly, there should be no soldering. The so-called false soldering, refers to only a small amount of tin soldered at the soldering point, resulting in poor contact, sometimes through sometimes broken. In order to avoid false soldering, should pay attention to the following points:
(1) ensure that the metal surface clean
If the surface of the weldment and solder joints with rust stains, dirt or oxides, should be scraped with a knife or sandpaper grinding before welding, until the exposure of bright metal, in order to give the surface of the weldment or solder joints plated with tin.
(2) Temperature control
In order to make the temperature appropriate, should be based on the size of the components to choose the appropriate power of the soldering iron, and pay attention to master the heating time. If you use small power soldering iron to weld large components or in the metal base plate welding ground, easy to form a virtual welding.
Soldering iron head with solder pressure in the weld, if you remove the soldering iron, the welded place a little solder does not stay or leave very little, it shows that the heating time is too short, the temperature is not enough or the welded object is too dirty; if you remove the soldering iron before, the solder downstream, it shows that the heating time is too long, the temperature is too high.
(3) The right amount of tin
According to the size of the required soldering point to determine the amount of soldering iron dipped in tin, so that the solder is enough to wrap the soldered object, the formation of a suitable size and smooth soldering point. If a tin is not enough, you can make up again, but must wait until the previous time on the tin together to be melted before removing the soldering iron.
(4) Choose the right flux
The role of the flux is to improve the fluidity of the solder, to prevent oxidation of the soldering surface, play a welding and protection. Soldering electronic components, should try to avoid the use of solder paste. A better flux is rosin alcohol solution, welding, in the place to be soldered on a drop can be.
