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384 Appendix A — Soldering and Safety Basics

Third-hand tool, Jameco part number 26690
Diagonal cutters, Jameco part number 146712

Needle nose pliers, Jameco part number 217891
Digital Multimeter, Jameco part number 220767
Desoldering braid, 0.075˝, Jameco part number 124118
Hookup wire, 22 gauge, 100 ft, Jameco part number 36792
Heat-shrink tubing, 0.12˝ diameter, 10 ft, Jameco part number 184721

The total cost of these items is a little over $100, and with them you can build and test just
about any circuit you can imagine. You can also fix many simple issues with electronic devices
in your home.

Soldering Iron
Soldering irons are rated by wattage. A higher wattage iron isn’t hotter, but has more heat
available to speed up heating up large items. For most hobbyist projects, a 25W to 35W iron is
all that’s needed. Do not use a solder gun. Those are 100W huge devices meant for large elec-
trical or plumbing work, not small electronic work. And in general, avoid cordless irons as they
can’t provide enough power and have tips not usable for electronics.
Another factor in soldering iron shopping is the tip type. Make sure the tip is replaceable. The
tip that comes with the iron will be fine when you’re starting out, but as you get more experienced
you’ll want to get a finer tip for working on smaller things. Replacing tips on most irons is
pretty easy, but you do have to let them cool down first. Certain higher-end irons allow you to
change the temperature of the tip either by a dial on the base or replacing the tip.

Buying a Soldering Iron
Don’t get the cheap $5 soldering irons you can find in electronics and tool supply shops. The
tips destroy boards and they only last a few months. Spend the money on a good iron. Weller
makes a decent 25W iron, the WP25, that’s about $33. The Weller WTCPS solder station
shown in Figure A-1 is a 42W iron and goes for around $130. A good iron lasts a long time.
The iron shown in Figure A-1 has been in use for almost 20 years, with the only maintenance
being tip replacement.
If you get an iron that doesn’t come with a stand, be sure to order one. They cost only a few
dollars and prevent a lot of mishaps. It’s easy for a hot iron to slip off a table and onto the floor
(or onto your lap). If you can, find one with a sponge holder because keeping the soldering iron
tip clean is essential to getting good solder connections.

Soldering Iron Care
A few pointers to extend the life of your soldering iron and make it work at its best:

Always keep the tip clean. Use a damp sponge (not dripping) and wipe off the tip before
and after use, although the tip is hot enough to melt solder.