After the pre-soldering treatment, the soldering iron can be formally soldered.
(1) Hold the soldering iron in the right hand. Hold the component or wire with sharp-nosed pliers or tweezers in the left hand. Before welding, the soldering iron should be fully preheated. Soldering iron head edge surface to eat tin, that is, with a certain amount of solder.
(2) Place the tip of the soldering iron firmly against the soldering point. The soldering iron and the horizontal plane at an angle of about 60 ℃. So as to facilitate the flow of melted tin from the soldering iron head to the soldering point. The time that the soldering iron tip stays at the soldering point is controlled at 2 to 3 seconds.
(3) Lift off the soldering iron tip. The left hand is still holding the component does not move. Wait until the tin at the solder joint cools and solidifies before releasing the left hand.
(4) Use tweezers to rotate the leads to make sure they are not loose, and then the excess leads can be cut off with offset pliers.
Welding quality ----- When welding, make sure that each solder joint is firmly welded and has good contact. To ensure the quality of welding, the typical characteristics of the tin point is bright, round and smooth without burrs, the amount of tin is moderate. The tin and the soldered material are firmly fused, and there should be no false soldering or fake soldering.
False soldering is only a small amount of tin soldered at the solder joint, resulting in poor contact, sometimes on and sometimes off. False soldering means that the surface seems to be welded, but in fact not welded, sometimes by hand, the lead can be pulled out of the solder joints.
When soldering a circuit board, be sure to control the time. Too long and the board will be burnt or cause the copper foil to fall off. When removing components from a circuit board, stick the tip of the soldering iron to the solder joints and pull the components out after the tin on the solder joints melts.
How to remove and replace components ------ In fact, the removal and replacement of components and then simple, with a solder sucker can easily be completed, the component pins on the solder all sucked off, here to tell you a little trick, most of the circuit boards are now fine workmanship, the use of solder is very little, it is very difficult to melt off, then we can add a little bit of solder in the pins and then go to the use of the solder sucker will be much easier.
Another method is mentioned earlier, the direct use of soldering iron to melt off the solder, but so there is no small danger, both to be careful that the solder joints are not completely melted, but also afraid of contact too long burned components. Commonly used method is to use tweezers to hold the components in the heating time to pull the outside, when the temperature reaches, the components will be pulled out, but remember not to be too hard, otherwise the pin broken in the solder in trouble.
Of course, for insurance purposes, the two methods used in combination is no better, because sometimes due to the component jack is too small, suction welding is difficult to be sucked clean, this time to remove the suction welding will stick, so you can use a soldering iron to heat to remove.
Soldering in fact is not so terrible, perhaps for the novice, the first try is more difficult to master, however, more practice will naturally skilled. In short, for enthusiasts who love to do it, as long as you practice more then master the tricks of the trade is sooner or later.
