What is Soldering?
Soldering is the act of heating up two or more pieces of metal, usually tin, copper or brass, that need to be joined and melting solder to join the pieces .
What is soldering used for?
Soldering is used in the plumbing industry, for making stained glass, for making jewelry and in electronics. We will concentrate on soldering for electronics as it has many applications. You can make cool new things or repair things like guitars or rc cars.
What types of soldering are there for electronics?
There are two basic types of soldering for electronics, through hole soldering and SMD or surface mount soldering. Most people who solder at home use through hole soldering as it is easiest. SMD soldering can use much smaller parts and can be done but won't be discussed here.
Why do I want to do it?
Soldering can be a fun way to build electronic kits or your own creations that light up, blink, make noise or perform some other function.
What do I need to start soldering?
You will need at least 3 things to start. A soldering iron or soldering station, solder and wire cutters. Of course you will also need what you want to solder.
What is the difference between a soldering iron and soldering station?
The main difference between a stand alone soldering iron and a soldering station is the ability to control the temperature. Stand alone soldering irons plug directly into an electrical outlet and then heat up to a certain temperature. The tip temperature is usually based on the wattage of the soldering iron.
The base of a soldering station plugs into an electrical outlet and then the soldering iron is plugged into the base. This allows you to control the temperature of the soldering iron by using the controls on the base.
What are the different types of soldering tips?
Both soldering stations and irons can be used with a variety of tips. In the image below top to bottom we see a hoof tip, conical tip and a screwdriver tip.
What are the different types of solder?
See our previous Solder vs Lead Free Solder for more details. but most home solderers use leaded solder.
How should I start?
Start by getting ready and setting up a clean area to work in. Make sure you have some kind of ventilation. An open window and a small fan are not ideal but can suffice to start with. Now turn on your soldering station or iron so it can heat up.
Now get your project PCB (circuit board) ready by putting it in a vise or helping hands. Now insert the component you wish to solder through the holes so that the lead stick out the bottom. The bottom is the side with the exposed copper pads.
If you don't have a project yet but want to practice soldering start with some perfboard and a small component like a resisitor or just some hookup wire..
Once the component is in place, bend the leads so it will stay in place while your are soldering. It should look something like this.
Now, hold the solder lead in one hand and the soldering iron in the other. Place the tip of the iron on the copper pad the component lead is stick out of. Make sure the soldering tip is also touching the component lead. Hold the iron here for 3 or 4 seconds and then apply the solder to the pad and the base of the lead. You may need to hold it here for a second or two before the solder starts to flow. Once there is enough solder remove your hand with the solder and then remove the soldering iron and put it safely away. Examine what you have done and trim the lead to the top of the solder you just added. It should now look something like the image below.
What should my soldering look like when I am done?
Your solder joint should look like a chocolate kiss or a volcano when you are done.
In the image below joint 1 is a good solder joint. Joint 2 is bad because it doesn't adhere to the copper pad. Joint 3 is bad because it doesn't adhere to the lead going through the sole. Joint 4 is bad because it bleeds over and connects to joint 5.
Use some kind of ventilation.
You can buy a fan, smoke absorber or make your own.
We made one once using an upside down plastic tub from Target, a fan and some left over dryer hose we stuck out the window. The fan then sucked away the soldering smoke. It wasn’t pretty, but it worked.
The point is don’t breathe in the fumes and use ventilation, ideally a fume extractor.
Also watch out for the very hot soldering iron tip and never touch it while soldering.
When you are done soldering make sure the soldering iron is off.
Wash your hands after soldering.