Soldering is connecting two pieces of metal so that electricity can flow through them with a metal alloy (solder). This can be used for attaching pins in the holes of a board (see below), to attach two wires together (see below), and many more
For more information about
the uses of soldering, look here:
[DA1]Types of solder can vary, but the most common is tin-lead. Lead free is also common. While leadfree is safer[DA2], it is not as easy to heat up, and often produces a worse soldering job. The temperature needed to melt leadfree is around 422
degrees Fahrenheit, whereas lead solder has a melting point around 361 degrees Fahrenheit.
For more information
about lead free vs. lead solder, click here:
Before You Start:
Wear goggles while soldering to protect yourself from splashes of the solder. A fan can also be important as a way to dissipate the fumes that the solder gives off. Gloves are not necessary
Be careful with the soldering iron because it gets very hot.
You should keep a damp sponge and some steel wool next to you. This is important for tinning the tip.
Tinning the Tip:
Cleaning and preparing the tip of the soldering iron is very important for getting a clean soldering job
. This process is called “tinning the tip.”
First allow the soldering iron to heat up to the temperature
you have set. Then, holding the tin-lead in one hand and the iron in the other, touch the tip of the iron to the tin-lead, so that the iron melts it. Allow the tin-lead to dry on the tip of the iron. You want to cover the tip of the iron with the tin-lead, giving it a uniform coat. To create the uniform coat, put the iron on the damp sponge and turn it so that all sides of the tip run across the sponge. If the tin-lead is clumped on one part of the iron, you can put the iron in the steel wool to help smooth it. For a video of the tinning, click here:video of the tinning
In this video, the guy uses a cloth as the damp sponge.
NOTE: Read everything before doing anything. (No, this is not like that test.)
After the tip is properly tinned, you are ready to solder. You will want to practice a few times before you solder your actual project.
Attaching pins to a board:
Often, when you order various
types of electrical boards (Arduino boards, GPS’s, etc.), the boards will come without any pins in them. In these cases, you will have to attach the pins to the board by soldering.
- Put the pins in the board, positioned as you want them (look at the picture of the board you ordered to help you figure out the positioning).
- On the side of the pins that you are not soldering, tape the pins in place. One large piece of masking tape should be perfect. If done properly, when you turn the board so that the side you are soldering is face-up, the pins should not move out of place.
- You will need both hands to solder, so put the board in a vise and attach the vise to the table to keep it from moving.
- Tin the tip of the soldering iron. (See above.)
- Holding the solder in one hand, touch the tip of the solder to the base of the pin, close to where the pin touches the board.
- Using the other hand, touch the iron to the side of the pin. The pin will conduct the heat from the iron to the solder, melting the solder to the pin. (See below.) You may need to touch the side of the iron to the pin (instead of the tip). Be careful not to touch the iron to the plastic itself. If you do, you will melt the plastic and make a mess. Getting a good joint takes some practice. See the picture below for a visual difference between a good and bad joint.
Two wires together:
Towards the end of your project, after you have made certain that the wiring of your circuit is final, you may want to solder two wires together in order to condense your circuit by removing alligator clips. This helps with the overall look of the project, making it seem more finished and professional.
- Twist the ends of the two wires together and put one of the wires in the vise. Make sure that the vise is secured to the table.
- Tin the tip of the soldering iron. (See above.)
- Holding the solder in one hand, touch the solder to the spot where the wires meet, where you twisted them together.
- Holding the iron in the other hand, touch the iron to the solder and the wires, so that the solder melts to the two wires, “gluing” them together.
- Make sure that the joint you created is good (see the picture below).
For a video of soldering two wires together, watch this: https://www.youtube.com/watch?v=BLfXXRfRIzY
Removing a bad soldering job:
If your soldering joint is bad, you can try to remove it by using the solder-plunger.
- Put the soldering iron on the soldering joint. This should heat up the solder there, which will allow the plunger to remove the joint.
- Put the plunger over the soldering joint and push down the lever at the top. Push it until it locks into place right, as far down as it will go.
- Keeping the hole of the plunger over the joint, push on the button on the handle. The black lever you just pushed down should pop back up, hopefully removing the joint with it.
For a video of the use of a solder-plunger, click here (work with the plunger starts at 0:59): https://www.youtube.com/watch?v=j-_pnc-Qqm8