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Certainly there are lots of electronics and kits that have entered Makers’ lives lately. Some people already know how to solder, but many people are just getting started. Amy posted a comment voicing her frustration at learning the seemingly guild like skill of soldering.

Below are my notes to Amy, which seemed like it would be handy information to others as well.

It can be done, this soldering thing.

Here are a few things that I try to keep in mind.
Workspace
Setting up on a reusable board or thick cardboard (not the corrugated kind) is good, because cleanup will be easy, and you won’t run the risk of messing up the table.

Soldering iron
A decent iron is nice, but a cheap one can do. Turn off the cheap irons when not in use, because the tip seems to dissolve if left on. You don’t need to spend lots of money on a fine expensive tool if you are just figuring it out. You can learn how to do it on a cheap or borrowed iron, then when and if you can recognize the difference and value, then spend the money or talk somebody into gifting you a good one. Lots of people like the temperature controlled ones from Weller.

Keep the tip clean. A wet sponge works, but I like steel wool better. Wipe the tip periodically. The sponge will cool the tip when you want it to be hot.

A soldering iron stand is good, but at least keep the business end of the iron from burning a hole through the board and onto the table.

Solder
Thin, lead free solder is good. Try to stay away from the lead based stuff. See the earlier comment about metals and the badness they cause.

Safety glasses
Most people only get one set of eyes. Replacements are difficult to have installed. You are better off to take care of the pair or one you have, than to get them repaired later. Wear your safety glasses while doing dangerous stuff.

Recognize the components:
Pretty much all electronic components have markings on them. Mostly they are done in small white print, but resistors are indicated with color bands. Look at the parts list, and search the markings on any components you are not familiar with. If you put a single diode or LED in backwards, that could be the problem that makes your circuit not work. Check and double check. Search for the things you have, and look at pictures of them. Check the documentation that comes with any kit you have for notes about what the components look like and how to handle them.

Looking at the pdf for the kit Amy mentioned, there are a few things that could slip you up. LEDs, transistors and capacitors are all polarized in this circuit. Make sure they are all in the right orientation. The transistor might be exotic, here is a page that has datasheets for it. l According to this page, you could use a 2N3904 to replace the BC547. The 3904 is a pretty common transistor, you should be able to harvest one out some junk device like a radio or toy.

Resistors are not polarized, but the color bands are completely essential to get right. Resistors regulate the flow of the current in the circuit. Electricity will always follow the path of least resistance. If you have a high value resistor in a place that calls for a low value one, electricity will not flow where it should. You can read them by looking at the colors. There are lots of great resistor color code calculators. Here is one that looks good, but there are many more online.

Multimeter
Resistance is measured in Ohms, often symbolized by an upside horseshoe, greek symbol for omega. If you can get your hands on a meter, you can set it for Ohms, and check your color band calculations against the numbers the meter will show. A multimeter is also handy to be able to check continuity and voltage. See this page for some info on how to use a multimeter.

Technique:
You are heating up the parts, not the solder. When the parts are hot enough, the solder will flow onto them. Touch the iron to the junction between the board and the component, let it heat up, then touch the solder to either the board or the component. Dumping it onto the tip will melt the solder, but often results in a cold solder joint.

Less is better in soldering
You should have the very least amount of solder needed to hold the component to the board. If you have blobby solder joints, you will likely have trouble with bad connections called cold solder joints.

Practice soldering
Sometimes it is a good idea to practice on junk. You can try soldering a wire onto a coin, US pennies work pretty good for that, they are mostly zinc with a bit of copper. Lots of other countries have other alloys, often with lots of aluminum in them, so I don’t know about that. Aluminum wicks the heat too fast, so it probably wouldn’t work.

You can also break apart an old radio or other device, cut some wires, get some parts and just solder some stuff together. After a bit you get the hang of it.

If you use the search box on any of the Maker Media sites and put in the word soldering, there are loads of resources that should help you get started.
You can watch the Make Weekend projects podcast on soldering, which is great.
Make Volume 1 had a primer on soldering.
Check out the post about a photo gallery of soldering basics.
Check out this great project for building your own fume extratctor.

There is lots of great information on soldering at Instructables.

This is not some mystical skill that people get handed to them from the tinkering gods. You learn it by doing it. You do it because you want to make something. You keep doing it because you want to make more interesting things. Learning this is just a process of getting some skills, and improving them by using them. Eventually, you can get to the point of designing your own circuits, but you can do lots of great things by following the path established by others. There are a small handful of tools that you can use with soldering and electronics. This kit has pretty much everything you need to get started.

Good luck, keep at it, and by all means, let us know about your progress.

You may have other tips for people who are new to electronics, kits and soldering. Please contribute your techniques and ideas in the comments. If you have photos and video, add them to the Make Flickr pool.

Chris Connors

Making things is the best way to learn about our world.


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