Operation Manual

you’ll see plenty of evidence of this. All the larger components are connected using what’s called through-hole soldering, where
the components’ leads are passed through holes in the printed circuit board and then soldered into place. Smaller components
are attached via surface-mount soldering.
Solder isn’t pure metal—it also contains a substance called flux, which is designed to etch away any tarnish on the surfaces to be
soldered in order to ensure as clean a join as possible. Most electronic solder includes three to five cores of flux. You can also
buy flux separately as a paste or in liquid form, although for most hobby soldering, this isn’t necessary.
When you’re starting a soldering project, make sure you have a clean, well-lit workspace. Also make sure the area is well
ventilated. Solder fumes aren’t very healthy, and while they’re extremely unlikely to build up to dangerous levels in low-volume
hobby soldering, it’s still a good idea to keep exposure to a minimum.
In addition, you should protect the work surface in some way. It’s not uncommon for small blobs of molten solder to fall, which
can burn and mark tables. You can purchase an anti-static workmat (see Figure 12-9 for an example), but a glossy magazine
works just as well. Don’t be tempted to use a few sheets of cheap newspaper—solder can burn through thin paper before it
cools.
Figure 12-9: An example soldering work area, with a protective anti-static workmat
If you’re doing delicate, close-up work, you should wear protective glasses. Sometimes the boiling flux inside the solder can
cause it to spit upwards, and if it hits you in the eye, you’ll be in for a world of pain.
Don’t let these warnings put you off soldering, however. Although solder is extremely hot, it cools quickly and burns are not only
rare but nearly inconsequential. Respect the equipment, but don’t fear it.
With your work surface chosen and protected, lay out your equipment. The iron should be placed on the side of your dominant
hand, and positioned so that the cable isn’t trailing across your work area. Make sure you can move the iron freely before
plugging it in. If the cable gets caught on something, you may end up burning yourself.
Dampen your soldering sponge with water—it should be damp, but not dripping wet. This is important: the damp sponge will be
used to clean the iron, and if it’s dry, it will burn and may damage the iron’s delicate tip.
It will take a few minutes for the soldering iron to reach its operating temperature. If you’ve purchased a temperature-controlled
iron, this will normally be indicated either by a light that switches on or off to indicate the temperature has been reached or by a
numerical temperature read-out. (See the operating manual that came with your soldering iron to find out how temperatures are
indicated on it.)
Once the operating temperature has been reached, it’s time to prepare the soldering iron using a process known as tinning.
Follow these steps:
1. Push the tip of the solder against the tip of the iron, allowing a small amount to melt onto the iron. Be careful not to melt too