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STORY 4: "How does the soldering iron work?"

Hikaru's diary on learning to solderHikaru's diary on learning to solder

How does the solodering iron work?

12|3
Mr. Fusamura

Now, let's start the repair.

Hikaru

First, I should remove the plastic insulation of the lead wire. (Photo 1) What do I do next?

Mr. Fusamura

You should suck up the solder from the motor terminal. Put the desoldering wire onto the terminal and press it with the soldering iron on the wire. (Photo 2) Be careful not to hold the soldering iron down for too long. Otherwise, the motor's plastic parts will melt.

Peel the lead wire coating.Peel the lead wire coating.
Photo 1
Put the desoldering wire onto the terminal and press it with the soldering iron.
Photo 2
Hikaru

This makes me nervous. Am I doing it right?

Mr. Fusamura

You're doing a good job Hikaru.

Hikaru

Thanks! Now, I'll wind the lead wire around the terminal (Photo 3) and solder the wire to the terminal (Photo 4). How is that?

Wind the lead wire around the terminal. Solder the lead wire to the terminal.
Photo 3 Photo 4
Mr. Fusamura

I'm afraid there's a problem with this.

Example of failure condition : Cold-Joint
Photo 5
Hikaru

What's wrong?

Mr. Fusamura

This type of soldering condition is called "Cold-Joint", an example of unacceptable soldering. (Photo 5) The surface is rough and has no brightness.