How To: Make your own capacitive stylus
If you don’t like the look of any of the styluses on the market you can make your own stylus out of an old pen – or anything else with a metal handle (an X-acto knife or a paintbrush with a long enough metal grip, for example). The conductive foam that chips come packed in is ideal for the tip of the stylus; you can buy a sheet for around $8 which would make a few dozen styluses. If the pen you’re using has a metal body from the tip to where you grip it you can use something like a toothpick or a cotton earbud cut down to keep a nib of conductive foam pressed in place at the end; if not, you can solder a piece of wire from the tip of the pen to the metal grip (put it on the inside of the barrel of the pen for neatness).
The conductive foam tip needs to be about 6-7mm across; if the hole in the pen isn’t big enough you’ll need to enlarge it – and make sure to file it smooth in case it ever touches the screen of your tablet.
If you have a solid metal pen or knife handle you can dip the end in conductive glue that you can make up from an insulator like Performix liquid tape or DAP Contact Cement mixed with carbon graphite powder (make sure to do the mixing outdoors or in a well-ventilated area) – or even use Crayola Model Magic clay to mold a tip over the end (that might also work in a pen as long as you pack the clay back as far as the metal grip your fingers will touch, but it shrinks as it dries so it might not keep enough contact to work).
To make a capacitive brush you need conductive thread (which you can buy online from Sparkfun.com); open the metal bristle holder on the brush, remove the bristle and replace them with conductive thread – you may need to unravel it to get flexible enough bristles. Check out the Instructables site for projects with step-by-step instructions – we especially like this, thisand this.