A soldering iron is a hand tool used in soldering. It supplies heat to melt solder so that it can flow into the joint between two workpieces. For well over 4000 years mankind has known how to join metals together by soldering. In the 1800s and early 1900s soldering irons were still heated by flame. Nowadays they are typically heated with electrical power and sometimes with burning gas.
Electrically powered soldering iron is composed of a heated metal tip and an insulated handle. Heating is achieved electrically, by passing an electric current through the resistive material of a heating element.For electrical and electronics work, a low-power electrically heated soldering iron, a power rating between 15 and 35 watts, is typically used. Professional typically use temperature controlled (thermostat) soldering irons that have somewhat higher ratings (often 40-80W).
The soldering iron temperatures used for electronics soldering are typically between 260 and 350 degrees celsius. Your iron will not melt metal if it is too cold and you will have a hard time soldering if the iron is too hot. If you use too hot iron, you risk damaging the circuit board and electroncs components. For electronics work a temprature controlled soldering station is preferred. There are variety of means are used to control temperature. The simplest of these is a variable power control, much like a light dimmer. Better soldering irons use thermostat control.
Here is thermostat controlled Velleman soldering station I use:
Soldering irons are easy to use but you will need a little bit of practice before you can do some precision work. For tips how to work with soldering irons, watch this Soldering basics and choosing a cheap soldering iron video.
There are some true classics in soldering iron market. There are a handful of manufacturers who make products that are legendary for lasting forever, and who still support their products made a lifetime ago. These are usually those who set the standards in their field.Weller is one of those companies. Long-Term Review: Weller Magnastat Soldering Iron article gives a review of one truly classic soldering iron model.
On the other side od the market are the very cheap soldering irons. To get idea how they are watch this Inside the cheapest soldering iron on ebay andEEVblog #596 – World’s Cheapest Soldering Station – Yihua 936 videos:
Here are some quick tips for safe soldering and desoldering when necessary:
Selecting Your Solder: For electronics works there are two main types of solder – leaded and lead free. Treaditionally soldering for electronics has been done with tin+lead solder (typically in 63/37 and 60/40 moxes). Leaded solder is easy to work with, but contains poisonous lead (make sure to wash your hands regularly to avoid absorbing it). Another option is lead-free solder. It does not contain lead, but the flux in lead-free solder is much more active than the rosin (literally pine sap) flux in leaded solder (typically much more irritating to your eyes and respiratory tract). To solder with lead free solder, you typically need to use higher temperature and soldering iron with better temperature control. A “good” lead-free solder joint is grainy and rough. If you do repair work, use the same solder type (leaded or lead free) that was originally used, because mixing leaded and lead-free solder can lead to unexpected results.
Catching Your Breath: Soldering produces fumes, and you don’t want to breathe them in. Ensure that your workspace is well ventilated (exhaust fan is a good idea).
Protecting Your Eyes: Safety goggles are an important part of any safe workspace. Spatter may be rare, but it’s always better to be safe than sorry.
Never forget that your soldering iron is hot! Make sure that you only hold it by the insulated grip, and always return it to its stand after you’ve used it.
A clean iron tip means better heat conduction. Use a damp sponge to wipe the still-hot soldering iron between uses. An alternative is to use solering iron cleaner with Brass wire sponge. How Is a Wet Sponge Used?