Good morning, Hikaru. Are you getting used to the company?

I'm so glad to hear that.
By the way, let's talk about various soldering methods today.

Yes. You have a good memory.
The number of electronic components used for P.W.B.s in electric products is very large.
If these components are soldered one at a time, it takes a lot of time and the soldering cost is staggeringly high. Furthermore, labor of soldering workers who handle so many components is very large.

Making a single product may be interesting, but in the case of mass production, you can't say that.

Today, I'll explain how to solder a large quantity of electronic components simultaneously.

Hey, watch your words.

You say one word too many.
Soldering methods are generally classified into three types: "Iron soldering", "Dip soldering" and "Reflow soldering". You know about "Iron soldering", don't you?

The "Dip soldering method" is the method of dipping a target part into melted solder. The target part is directly heated with melted solder. It can be illustrated like this:

The container that stores melted solder is called the "solder pot" or "solder bath".
Our product, HAKKO FX-305, HAKKO FX-301B, corresponds to this. But, HAKKO FX-301B is generally used for pre-tinning of relatively small P.W.B.s and wiring.
For dip soldering, it is important to control the temperature of solder in the bath, and the concentration of impurities in the soldering bath. Otherwise, metal in the patterns and target parts will melt into the soldering bath.
The temperature of solder in the bath is set about 30 to 80℃ higher than the melting point of solder.

But, this method causes oxidization of the solder surface, resulting in a soldering failure.

Yes. In particular, tin in the solder will combine with oxygen in the air.
To prevent oxidization, we must frequently remove the oxide film on the solder surface.
The flow solder bath was devised so that the solder surface remains free from the oxide film. Flow soldering is the most popular method.
The principle of the flow solder bath can be illlustrated like this.

That's right. Our product, HAKKO 485, corresponds to this.
But, since the solder bath always has a new solder surface, it will be oxidized one after another. Consequently, the amount of resultant oxide increases.

Yes. The components are fixed with adhesive before soldering. But, to solder surface mounting components, the reflow soldering method is generally used.

What are you talking about?
Reflow soldering is the method of applying solder to a pattern with any method.

You ask a question about everything. Stop asking questions until I explain it to you!
For example, one method is preliminary solder plating, or placing the solder that has been formed into a shape suitable for the purpose of use, such as disk, washer and global shape onto flux. Another method is solder paste printing, or pasting a mixture of flux and solder powder onto a pattern.
Generally, the solder paste printing method is used.
After applying solder onto a pattern, put a target component onto it. Then, the solder is melted with a certain heat source to solder the component.
This method is classified into infrared reflow soldering, laser reflow soldering and so on, depending on the type of heat source.
It can be illustrated like this:

Ha-ha-ha-ha-ha (Laughing) It looks like a pizza, as you say.

No, that's not always true.