Introduction to lead soldering and how to use it

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A method that is frequently utilized in the electronics sector is lead soldering. So, how precisely does one employ this technique? To discover more about this method, continue reading the article below!

What is lead soldering?

Lead soldering is a technique for joining two metals together using a soldering iron and a molten tin and solder solution. After this solution cools, it will form a strong bond between the two metals. This technique is mainly applied to soldering electronic components.

lead soldering

View more: Solder Paste

View more: Solder Bar

View more: Solder Wire

Tools and materials to prepare when soldering lead

Before performing soldering, you must prepare the following tools and materials:

Lead soldering iron

A soldering iron is an indispensable tool when soldering lead. The effect of the soldering iron is to melt the solder around the joint.

Welding torches have many different capacities, but the most commonly used is a 40-watt welding torch. Because using welding torches with a larger capacity will cause many disadvantages, such as:

  • The more powerful the soldering iron, the more heat it generates. When in contact with components, it is possible to damage components by overheating.
  • This causes surface oxidation of copper conductors because the heat of the soldering iron is too large. From there, the weld will become more difficult to weld.
  • It is possible to blacken at the welding position, reducing the gloss as well as the aesthetics of the weld.

lead soldering


Rosin is applied to the surface of the solder connection during lead soldering to assist prevent oxidation and lengthen the life of the weld. The rosin also helps the weld increase adhesion at the same time. Rosin is often solid and light yellow in color when used in welding.

lead soldering

Solder/Lead Solder

The lead soldering process is definitely indispensable for soldering tin (also known as solder lead). This is a metal alloy that can be melted to form a solid joint for two metals. Currently, the solder used in lead soldering has two main types: leaded solder and lead-free solder. However, lead-free solder is preferred. Because its composition is not toxic and it does not produce toxic fumes, it is safe for human health.

lead soldering

The most detailed soldering operations

Step 1: Clean the surface to be soldered, the circuit board, and the component feet. This step is necessary to increase the quality and aesthetics of the weld.

Step 2: Cut the component pins so that the pins, when plugged into the circuit, still protrude about 1mm from the surface of the circuit board to the component.

Step 3: Perform tin coating at the tip of the soldering iron, the wire end, and the position to be soldered. The tin coating step is used to help the soldering iron not come into direct contact with the component pins and circuit boards. At the same time, giving adhesion to conductors and components when soldering. As well as helping to dissipate heat around the soldering position without damaging or burning the circuit board due to excessive heat.

lead soldering

Step 4: Solder components

For common components:

  • Bring the turpentine closer to the torch so that the turpentine flows into the tip of the torch.
  • Bring the soldering iron to the foot of the component, increase the temperature to allow the resin to flow out, and cover the component pin and hole in the circuit.
  • Put tin wire into the areas of component pins, printed circuit holes, and soldering iron tips. At this time, the tin that touches the tip of the soldering iron will melt, and when it cools down, it will form a strong joint.

For multi-pin components:

  • Apply turpentine to the entire pins of the chip.
  • Take a pea-sized amount of tin for the first pin, heat up the soldering iron to melt the tin, and move on to the next pins until the last pin. Note that you have to move in one direction.
  • Any component feet that still touch each other can add turpentine and continue to move until the end.

Note: During the soldering process, you can add or subtract tin as you like to beautify the solder joint.

Above are answers to questions related to lead soldering. Hopefully, through this article, you have grasped the detailed operations when performing lead soldering.

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