A soldering iron is a hand tool used in soldering. There are many soldering irons available on the market. They come in a variety of sizes and shapes. Which soldering iron to choose for yourself depends on the soldering projects you are planning to do, as well as how often you are planning on using it.
The four main factors to consider when choosing a soldering iron are:
1) wattage
2) type of the soldering irons
3) temperature control
Wattage
The wattage of the soldering iron is one of the most important factors of a soldering iron. Most soldering irons used in the electronics are in the range of 20 – 60 Watts. Soldering irons with the wattage of 50W is very common these days and it will provide sufficient heat for most of soldering projects on the circuit boards. Soldering irons with higher wattage (40W -60W) are better. It does not mean that soldering irons with higher wattage apply more heat to the solder joint - it means that soldering irons with higher wattage have more power available. Since most of soldering stations come with a control knob on power stations for setting the iron’s temperature, it is possible to regulate the amount of heat on iron tip.
Generally, there are 4 different types of soldering irons:
-Soldering pencil
-Soldering station
-Soldering systems (rework /repair stations)
-Soldering guns
-Gas Irons
Soldering stations
Soldering stations
Soldering stations consists of a soldering pencil attached to a power station. The power station has a control for setting the desired temperature on the tip of soldering iron. Some soldering stations come with electronic temperature control - that means you can very precisely set and maintain the temperature of the iron. The power station automatically keeps the iron tip at an appropriate temperature. Soldering stations can cover most of soldering projects including soldering of through-hole components, and very fine surface-mount components as small as 0603 and 0805.
Rework/repair systems are complex soldering systems which are mostly used in industry or in the high-volume manufacturing facilities. Soldering systems usually consists of several hand pieces including soldering iron, hot-air gun, de-soldering gun, thermo-tweezers, etc.
Soldering guns
Main part of a soldering gun is a transformer which converts 220 V AC to a lower voltage. A secondary winding of transformer has only one turn. This way the secondary of transformer produces very low voltage and several hundred amperes of current since primary of transformer is connected to 220 V AC and the secondary winding of transformer has only one turn. This high current is routed through copper tip of soldering gun and as result the tip of soldering gun is quickly heated by the high current flowing through it.
Soldering guns can be quickly and easily turned on and off and they have a very short warm up time. However, I do not recommend using a soldering gun for fine work on circuit boards since they can generate too much heat and can therefore damage circuit boards or the components on it.
A gas iron allows you to solder without the restriction of having to find a power source, ie 220v ac. Ideal for work out in the field or in those hard to reach places, and fire up in seconds.
