Soldering Iron Welding Technology: How to Use a Pointed Soldering Iron
1. Safe use of soldering iron
Use the ohm setting of a multimeter to measure whether there is an open or short circuit at both ends of the plug, and then use the Rx1000 or Rx10000 setting to measure the resistance between the plug and the shell. If the pointer does not move or the resistance is greater than 2-3MΩ, it can be used safely without leakage.
2. Initial use of the new soldering iron
The new soldering iron cannot be used right away. You need to coat the soldering iron tip with a layer of solder first. The method is: use a file to clean the soldering iron tip, turn on the power, and when the temperature gradually rises, apply rosin on the soldering iron tip. When the rosin smokes and the soldering iron head begins to melt the solder, place the soldering iron head on sandpaper with a small amount of rosin and solder and grind it on all sides, so that the soldering iron head can be coated with a layer of solder .
3. The soldering iron is not hot or not too hot after it is connected to the power supply.
1) Check whether the power supply voltage is lower than AC210V (normal voltage should be AC220V). Too low voltage may cause insufficient heat and difficulty in soldering.
2) The soldering iron tip is oxidized or the fastening part between the root end of the soldering iron tip and the inner wall of the outer tube is oxidized.
4. Causes of neutral line electrification
In a three-phase four-wire power supply system, the neutral wire is grounded and has the same potential as the earth. If the neon bulb glows when tested with a voltage test pen, it indicates that the neutral line is charged (there is a potential difference between the neutral line and the earth).
An open circuit in the neutral line, an increase in the grounding resistance of the neutral line, an open circuit in the ground down conductor, or a grounded phase line will all cause the neutral line to be electrified.
Soldering technology of electric soldering iron:
1. Choose appropriate solder, low melting point solder wire for welding electronic components.
2. Flux, use 25% rosin dissolved in 75% alcohol (weight ratio) as the flux.
3. The electric soldering iron must be tinned before use. The specific method is: heat the electric soldering iron. When the solder has just melted, apply flux, and then apply solder evenly on the soldering iron tip so that the soldering iron tip can be evenly coated. A layer of tin.
4. For welding method, polish the pads and component pins cleanly with fine sandpaper and apply flux. Dip an appropriate amount of solder with the tip of the soldering iron and touch it to the solder joint. After all the solder on the solder joint melts and immerses the lead of the component, gently lift the tip of the soldering iron up along the lead of the component and away from the solder joint.
5. The welding time should not be too long, otherwise it is easy to burn the components. If necessary, use tweezers to clamp the pins to help dissipate heat.
6. The solder joint should be in the shape of a sinusoidal wave peak, the surface should be bright and smooth, without tin thorns, and the amount of tin should be moderate.
7. After the soldering is completed, use alcohol to clean the remaining flux on the circuit board to prevent the carbonized flux from affecting the normal operation of the circuit.
8. The integrated circuit should be soldered last, and the soldering iron should be reliably grounded, or the residual heat should be used for soldering after power failure. Or use a special socket for integrated circuits, and then plug in the integrated circuit after soldering the socket.
9. The soldering iron should be placed on the soldering iron stand.
