Learn to solder
Introduction to Soldering
My favorite guide to learn soldering is this comic by the great Mitch Altman, inventor of the TV-Be-Gone.
We also have a book Richtig löten (in German) in our lab library that gives more detailed advice.
Our lab uses Hakko FX888D soldering irons. They're the blue&yellow ones, and the favorite model of engineers at companies like SparkFun. The instruction manual is essential if you need to change any settings (but you normally don't have to).
Use leaded solder — it's easier to work with, the fumes are not as toxic, and you can see if your joint is good (shiny). Wash your hands after soldering.
Don't turn up the heat. It won't make a better connection, just burn out your board traces and the tip quickly. Clean your tip by wiping it on the brass sponge to remove solder, then on the wet sponge to remove oxidization, then dip it into the tip tinner for a fresh coating before every soldering joint. Clean your soldering connections with a flux pen before soldering, and you will get perfect soldering joints within 1-2 seconds every time. If you don't get your solder to become shiny and flow, you may need to use more flux, or (for large solder points) a bigger tip to transfer more energy more quickly. Increasing the temperature won't help. Our stations are password-locked to 350 degrees Celsius for that reason. Talk to a Fab Lab master if you need a different temperature.
A good beginner's kit to learn soldering is SparkFun's WeevilEye interactive lightup bug.
- Jan Borchers