I find sketching on the iPhone not too fun nor precise. The Pogo stylus, which is currently being used in Apple store iPod-touch-based checkout device, allows you to write on the touch screen with the pen form factor. It’s shiny and elegant, but I would rather hack some existing materials that I already have, especially a pen with the right balance and grip size.

Inspired by a blog post in Makezine about DIY iPhone Stylus, I decided to make one with my Staedtler mechanical sketch pencil.

Few technical notes:

• the stylus mimics a human finger tip, which must have enough conductivity, capacitance, and contact surface area to trigger the touch sensor in the iPhone capacitative sensor screen. After a few experiments, I found that the 9mm snap button works the best.
• I chose Staedtler Mars technico because it has the right weight, balance, and conveniently with a metal grip that would increase the capacitance of the stylus.
• as mentioned in the Makezine post, attaching the snap button with dental floss instead of super glue allows it to flex in different angles, thus always maintain the biggest contact area. Also, the snap button and Staedtler Mars tip makes a good ball-socket joint.

Materials:

• Staedtler “Mars technico” mechanical sketch pencil
• Dental Floss
• 9mm snap button

Voila, iPhone Stylus it is:

I am really interested an further testing my DIY stylus on a Macbook and Inklet, an application that turns the Macbook trackpad into a drawing tablet. If the system works, it would be much easier for people to draw sketches without buying a separate Wacom tablet. One example is that, designers can meet with the client in a coffee shop and sketch their ideas on the laptop without any extra drawing tablet.