Page 172 - Making things move_ DIY mechanisms for inventors, hobbyists, and artists

Chapter 6 Options for Creating and Controlling Motion 151

Solid wire is just that—a long, solid piece of wire that is covered with plastic insulation.
Stranded wire is more flexible, but solid wire is stiffer, so it’s easier to plug into
breadboards. Wire size is measured in gauges. The wire spools specified above are
22 gauge, which works well in breadboards (the higher the gauge, the thinner the
wire).
To strip the plastic insulation off the ends of a piece of wire from your spool, you need
to find the groove at the end of your wire strippers that corresponds to the wire
gauge number. Place the piece of wire in this groove with about 1/4 in of wire sticking
out of one side. Then squeeze the wire strippers together on and off while you rotate
the wire. This will cut the insulation but not the wire itself. Once you see a cut all the
way around the wire, pull the insulation off with your fingers. Follow the same steps
for the other end of your wire piece, and you have your own jumper wire!

Shopping List:

• DC toy motor
• Corresponding battery (9V used here) and snap or holder with wire leads (like
RadioShack 270-324)

• On/off toggle switch (like SparkFun COM-09276) or other SPST switch
• Breadboard (like All Electronics PB-400)
• Jumper wires (like SparkFun PRT-00124) or hook-up wire to make your own
(as just described)

Recipe:

1. Solder jumper wires to the legs of the switch and the terminals of the motor
(if they don’t already have wire leads). On DC motors, it doesn’t matter which
terminal is which, so you can just pick one.

2. Plug one leg of the switch into one of the breadboard columns marked with a
plus (+) sign and the other to a row of your choice on the breadboard. Turn
the switch to the off position.

3. Plug the red wire of your motor into that same row, and the black wire to one
of the breadboard columns marked with a minus (–) sign.