Presumably many people studied soldering in the electronic work lessons at school and I think this experience causes trouble with soldering in small scale.
In the class of the electronic work you learn “you must not heat a part for a long time” but in modeling it is the most important to heat a part enough.
Well, I will clarify the mechanism of soldering before detailed exposition.
Soldering mechanism is to compose 3-6 micron alloy between metal and solder by heating metal and to stick metal and solder by this alloy.
The melting point of the solder is about 185? (365°F). So if you heat the part about 250? (482°F) you can solder the metal well.
1.Selecting the soldering iron
First - classified roughly - there are two kinds of soldering irons: Nichrome heater type and Ceramic heater type.
Nichrome heater type is cheap, but the thermal efficiency is bad. Ceramic heater type is slightly expensive, but the thermal efficiency is good.
So if you don’t have soldering iron yet, I recommend a Ceramic heater type to you.
Then, I think you want to hear this most, I speak about the heat capacity of a soldering iron.
For your better understanding, I explain the heat capacity of Nichrome heater type as an example.
So for heating up a part enough when you assemble general etching part, I think a 40w soldering iron is the best. The heat capacity is enough and size is easy to handling.
If you assemble only an OVM clamp or accessories, a 20-30w may be enough. But as soon as you want to assemble 1cm² over slightly larger parts, 20-30w one’s heat capacity is not enough and you will feel stress.
And if you want to build big parts like the armor plate, a 60w+ iron will be necessary for you.
Well, there is another big factor in heating efficiency besides iron’s heat capacity; shape and size of the iron tip.
On the one hand the sharp and thin tip is easy to handling for close work, but since it cannot radiate heat enough like a large-capacity iron it is unsuitable for the assembling of a big part.
On the other hand, using a large-capacity iron, if you change the sharp and thin tip, you don’t have to worry to heat a part too much.
By the way, I use a 35w Ceramic heater iron where the exchange of the tip is possible. The heat capacity is equivalent to a 60w+ Nichrome heater type, but the size is smaller than of a 40w Nichrome heater type.
In addition I have good control of several kind of tips, I have not felt stress with this on assembling any kind of size.
?From the top to down: 35w Ceramic one, 30w Nichrome one, 40w Nichrome one, 60w Nichrome one
?This is my tips collection. There are a lot of tips, but I am usually using only the two on the left.
2. Tools which you should prepare
1.) Iron stand
For your safety an iron stand is absolutely necessary. There are persons who substitute it with an ashtray but I think you better don't do so.
I use a stand with a wet sponge to wash the iron tip.
I use a ceramic tile as working surface. A wooden board can also be used.
This is indispensable to soldering! You should utilize an appropriate material!
3.)Solder and flux
Various kinds of solders and flux are available, you should choose thin solder wire for general metal and liquid flux.
3.)Cutting and cleaning tool
These tools are called “Kisage” in Japan. But I don’t know what these are called in English.
In soldering, Kisage is the general term of the tool to use to remove unnecessary solder.
Depending on the use, you may prepare several kind of chisels and stainless steel wire brush like shown in the photos.
4.)Tools for part fixation
In soldering, part fixation is very important to solder a part at the correct position.
the blu tack is easy to obtain and is the most useful.
Hackle pliers (Fly tying tool) are most suitable to hold two pieces of plates solidly. Various sizes are sold in lure fishing shop, you should get yourself two or three different sizes.
Besides these, medical forceps are useful too.