Introduction to welding technology of electric soldering iron
The soldering technique mentioned here refers to the fusion between metal conductors and solder commonly used in the production of electronic circuits. Solder is a lead-tin alloy with a melting point of about 183 degrees. Commercially available solder is often made into strips or filaments, and some solders also contain rosin, which is more convenient to use.
1. How to hold the soldering iron
There are usually two ways to hold the soldering iron: the pen method and the fist method.
(1) How to hold a pen. Suitable for lightweight soldering irons such as 30W internal heating. Its soldering iron head is straight, and the head end is filed into a bevel or conical shape, which is suitable for soldering pads with a small area.
(2), fist method. It is suitable for high-power soldering irons. We generally do not use high-power soldering irons for electronic production (not introduced here).
2. Several methods of soldering leads on printed circuit boards.
There are two types of printed circuit boards: single-sided and double-sided. The through holes on it are generally non-metallized, but in order to make the components soldered on the circuit board more firmly and reliably, most of the through holes of the printed circuit boards of electronic products are now metallized. The method of soldering the leads on the ordinary single-sided board:
(1) Straight through the cutting head. The lead wire goes through the through hole directly. When soldering, make an appropriate amount of molten solder evenly surround the tin-stained lead wire above the pad to form a cone shape. After it cools and solidifies, cut off the excess lead wire. (see the blackboard for the specific method)
(2), buried directly. The lead through the hole is only exposed to an appropriate length, and the molten solder buries the lead tip inside the solder joint. This kind of solder joint is approximately hemispherical. Although it is beautiful, special attention should be paid to prevent false soldering.
