How to make your own capacitive touch stylus… sort of.
A video at metacafe has made the rounds through the DIY blogs that demonstrates how to make your own stylus for the iPod touch, which presumably would work on other capacitive touchscreens, as we’ve seen Rob do on the HP tx2 with the Pogo Stylus. It’s an impressive trick, but if you know how capacitive touch works, you’ll hear within the first ten seconds the author doesn’t really understand why his stylus works. Not to ruin the surprise, but basically for something to work as a capacitive touch stylus it must be sufficiently conductive, such as a metal pen with a brass snap fastener attached on the end that conducts electricity between you and the screen. If you think ”any pen will do,” well, you’re in for some disappointment.
In my own testing, I found I can use a brass tack to navigate my iPhone screen as long as I’m holding it with my fingers (pointy end toward me, rounded head against the screen). But it won’t work if it’s stuck on the end of a dry sponge because a dry sponge isn’t conductive. Works fine with a damp cellulose sponge though. In fact, the damp sponge worked as a stylus entirely on its own. So there you go: glue a damp sponge to the end of a stick and you got yourself a capacitive touch stylus. Cheap and absolutely won’t scratch your screen, unlike say, a metal snap fastener.