Step 2: How It Works
Oogoo II-A Conductive Rubber
You can make your own conductive rubber from silicone caulk, corn starch and graphite powder. This creates a silicone rubber which can be made thin enough to paint on or thick enough to cast into molds. While it is not as conductive as wire or conductive thread, it is more than conductive enough to make a variety of capacitive stylus.
The standard stylus for a capacitive screen uses conductive rubber or conductive foam to replace your finger on the screen. Every persons body has a small capacitance. When you touch a capacitive sensitive screen, you change the capacitance where you touch. Such screens are designed to detect changes in capacitance and locate exactly where they are on the screen. When you hold and touch a conductive stylus to a screen your capacitance is transferred to the screen and detected by its sensors.
Transparent Stylus Tip
Two of the stylus made in this instructable use VeilSheild conductive fabric as the stylus tip. Because this fabric is 70% transparent it allows you to see exactly where you are touching the screen. The conductive fabric is glued to a conductive metal handle which transfers the bodies capacitance to the screen.