Why use rosin with an electric soldering iron, how to choose one, and how to choose one
Choosing a suitable electric soldering iron will help greatly improve the efficiency of our soldering iron tip in electronic lead-free soldering, but usually, the choice should be based on the actual situation of the object to be welded, and generally focus on the heating form, power size, and soldering iron tip. shape etc.
According to the choice of electric soldering iron heating form
1. Choice of internal heating and external heating: Under the same wattage, the temperature of the internal heating soldering iron is higher than that of the external heating soldering iron.
2. When low-temperature soldering is required, use a voltage regulator to control the temperature of the electric soldering iron. The temperature of the electric soldering iron is closely related to the power supply voltage. In actual use, the temperature of the electric soldering iron is often lowered by lowering the power supply voltage.
3. Control the temperature by adjusting the extension length of the soldering iron tip.
4. There are mainly the following methods to stabilize the temperature of the electric soldering iron: install a stabilized power supply to prevent changes in the power supply network; maintain a certain volume, length and shape of the soldering iron head; use a constant temperature electric soldering iron; keep the indoor temperature constant; avoid natural wind or Electric fan etc.
According to the choice of soldering iron power
1. When soldering resistance-capacitance components with small wattage, transistors, integrated circuits, pads of printed circuit boards or plastic wires, it is advisable to use a 30~45W external heating type or a 20W internal heating type electric soldering iron. It is best to use a 20W internal heating type electric soldering iron in the application.
2. When welding the welding points of general structural products, such as wire rings, wire claws, heat sinks, grounding soldering pieces, etc., it is advisable to use a 75~100W electric soldering iron.
3. For large solder joints, such as welding metal rack tabs, solder tabs, etc., it is advisable to use a 100~200W electric soldering iron.
Why do electric soldering irons use rosin
In the past few days, I often see people asking why rosin should be added to solder. Here I roughly summarize it. Rosin is the most commonly used flux, neutral. If it is a newly printed circuit board, apply a layer of rosin perfume on the surface of the copper foil before soldering. If it is a circuit board that has already been made, it can be directly soldered. In fact, the use of rosin depends on personal habits. Some people will dip the tip of the soldering iron in rosin after soldering a component. The use of rosin is also very simple, just open the rosin box and dip the tip of the energized soldering iron on it. If solid core solder is used for welding, it is necessary to add some rosin; if rosin solder wire is used, rosin can be omitted.
The role of rosin in soldering. Rosin will have weak acidity at the temperature of the electric soldering iron, which can clean the oxide layer on the soldering surface, so that the solder can infiltrate the soldering surface. Nowadays, there will be rosin in the middle of the solder used in the general electronics industry. Just dip some on the electric soldering iron, and the solder wire will go directly to the electric soldering iron to work. The types of flux can be roughly divided into three series: organic, inorganic and resin. Resin flux is usually extracted from the secretions of trees, which is a natural product and is not corrosive. Rosin is the representative of this type of flux, so it is also called rosin flux. Because flux is usually used in conjunction with solder, it can be divided into soft solder and hard solder corresponding to solder. Soft fluxes such as rosin, rosin mixed flux, solder paste and hydrochloric acid are commonly used in the assembly and maintenance of electronic products. In addition, they should be selected according to different welding workpieces in different occasions. When using flux, it must be applied in an appropriate amount according to the area size and surface state of the workpiece to be welded. If the amount is too small, the welding quality will be affected. If the amount is too much, the flux residue will corrode the components or deteriorate the insulation performance of the circuit board.
