Hardware Hacking 19Chapter 6: How to Solder
You will need:
- A soldering iron with a fine tip.
- A small damp sponge (or folded paper towel in a pinch.)
- Rosin-core solder.
- Diagonal wire cutters.
- Wire strippers.
- Some light gauge insulated wire.
Soldering is one of the fundamental skills of hardware hacking. It is almost
impossible to hack hardware without knowing how to solder. As a skill it
commands a lower hourly wage than Java, but your friends and parents will be
very impressed at your acquisition of such arcane knowledge (as if you had
learned fire eating or Linear B.)
Successful soldering, like fundamentalist Christian comedy performed in mid-
winter by an L-Dopa patient, depends on cleanliness, heat, steady hands
and.....timing!
Soldering is not a question of dropping melted solder onto a joint. Rather, one
must first melt a thin layer of solder onto each surface. Then let them cuddle up
to one another while you heat both surfaces to re-melt the solder until it
commingles to form a strong bond. The process is similar to gluing wood: the
strongest bond comes from permeating the surfaces of both pieces of wood with
a layer of glue before assembly, rather than just squeezing a blob of glue between
them.
We will begin by practicing soldering wires together -- high temperature
knitting.
- Plug in the iron and place it somewhere where the tip will not make contact
with flammable/meltable/scorchable surfaces or the power cord (they make cute
little wire rests for this purpose.) Wait a long time for it to warm up. The iron is
hot enough to use when solder touched to the tip melts.
The tip of the iron must be smooth and clean enough that the solder flows
evenly, leaving a shiny silver coating. If blobs of solder fall off and the tip
remains grey & crust, unplug the iron and, after it has cooled down, polish the
tip with steel wool, fine sandpaper or a file. If the tip of the iron is seriously
pitted you will need to replace the tip (or, if it is a cheap iron with non-
replaceable tip, the whole iron.)
- Strip the about 1/2” of insulation from the ends of two pieces of wire. Use the
adjustments on the strippers (or a fine sense of touch) to avoid nicking the wire.
If the wire is stranded, twist the strands to eliminate frazzling. Hold the wires in
something so that the tips are up in the air but don't wiggle. You can use a fancy