You may not know it, but your old computer CD ROM drive is a treasure chest of useful components. Inside you’ll find stepper motors, rare earth magnets, bearings, and coils. It’s enough futuristic-looking greeblies to construct your own Star Wars prop, or maybe even your own portable CNC drawbot.
To prove the point of what can be done with a few repurposed CD ROM drives, Norbert Heinz popped open a pair, stacked them perpendicularly, wired up their stepper motors to a pair of H-bridge driver boards, and controlled his new creation with a Raspberry Pi.
The result is a CNC Pen Plotter that can move on an X/Y axis. To take it further and add the ability to have the pen automatically lifted from the surface (on the Z axis), Norbert added a simple servo to lift or drop the lightweight metal arm that attaches the pen to the unit.
You can find the full instructions for creating this DIY plotter posted here, along with the video walkthrough.
I love this project both for its small size and its creative reuse of cheap, old technology. It’s also great to see how Norbert took deliberate steps to make the device portable, including a Wi-Fi adapter to send bitmap image data to the Pi, and adding a lead-acid battery to get enough power to both the motors. That said, if you don’t have a large battery handy, the project can quickly get off the ground with conventional benchtop power supply or probably even a basic breadboard power supply.
So hack away, and show us what you create! You can tweet your creations to me if you feel so inclined. And for more inspiration on scavenging interesting components from old technology check out Make: magazine’s guide to tearing down an old computer printer.