Soldering facts for kids

Soldering a wire

Soldering is a cool way to join two or more metal pieces together. You use a special tool called a soldering iron to heat the metals. Then, a filler metal called solder melts and flows into the joint. The solder mixes a little with the metal pieces, creating a strong connection.

This type of soldering is often called soft soldering. This is because the solder melts at a temperature below 400°C (752°F). Some metals, like iron, are not usually soldered this way because they need much higher temperatures to melt. Solder used for electronics often contains a special chemical called flux. Flux helps clean the metal surfaces, making the solder stick better. A tool called a helping hand can make soft soldering much easier.

What is Desoldering?

Sometimes, you need to take apart things that have been soldered. This process is called desoldering. It means removing the solder so the metal pieces can separate. You can do this by heating the solder with the soldering iron until it melts. Then, you can gently pull the pieces apart.

There are also special tools to help with desoldering:

• Solder wick: This is a strip of very thin copper wires woven together. When you place the wick between the soldering iron and the melted solder, the wick soaks up the solder. This allows you to easily separate the metal parts.
• Desoldering pump: This tool looks like a tube with a small hole and a plunger. You push the plunger down, place the small hole over the melted solder, and then press a button. The plunger quickly springs back up, creating suction that sucks the melted solder into the pump.

Where is Soldering Used?

Soldering is used in many different areas. You can find it in plumbing, electronics, and even when making jewelry or musical instruments. It creates connections that are strong but can also be undone if needed.

Soldering in Plumbing and Metalwork

Soldering helps connect copper pipes in plumbing systems. It also joins sheets of metal for things like food cans, roof flashing, and rain gutters. Even car radiators use soldered parts.

Soldering for Jewelry and Tools

Many jewelry parts are put together using a higher-temperature method called silver soldering. This process is also used to fix or assemble machine tools and some parts in refrigerators. Small metal pieces are often soldered or brazed (a similar process). Soldering is also important for making stained glass windows, joining pieces of lead or copper foil.

Soldering in Electronics

In electronics, soldering connects electrical wiring and tiny electronic components to printed circuit boards (PCBs). The solder, which is a metal alloy, melts and joins the wires or components to the PCB. This can be done with a soldering iron, a special wave bath, or even a specialized oven.

Soldering Musical Instruments

Musical instruments, especially brass and woodwind instruments, use both soldering and brazing. The main body parts of brass instruments are often soldered together. Smaller parts like keys and braces are usually brazed for a stronger connection.

Images for kids

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  Small figurine being created by soldering

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  Soldered copper pipes

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  Solder

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  Lead-free solder

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  A tube of multicore electronics solder used for manual soldering

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  An improperly soldered 'cold' joint, where the wire was not sufficiently heated

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  Broken solder joints on a circuit board. The joint on the right, although unbroken, has separated from the board.

See also

In Spanish: Soldadura blanda para niños