Rather than toss out his old CD-ROM drives, Maker “NeumiElektronik” decided to transform them into a small, two-axis CNC laser machine capable of engraving materials like foam, leather and wood, as well as exposing pre-coated photo-resist PCBs. The total work area of this tiny unit is 3.2cm x 3.2cm (1.2” x 1.2”).
The project consists of a pair of CD drive stepper motors, two L298 motor drivers, an Arduino Mega (ATmega2560) and a 150mW 405nm laser. As Neumi explains, a Processing sketch generates strings from a .PNG or .JPG file and then sends them via serial to the Arduino, which drives the steppers to move the table and trigger the laser. Meanwhile, a TTL driver is used to manage the laser, which can be controlled by a joystick.
Burning time is set in the Arduino code, and pictures must be imported manually and placed in the folder, where the Processing sketch is located. Users can select the exposure time, depending on the material. Neumi notes that, “if you engrave photo-coated PCBs, it’s possible to harden the surface and create your custom made PCBs. The resolution is at about 100 pixels/cm.”
“In future versions, I might implement a transmission of gray scales to change the exposure time on the laser while the laser is operating,” Neumi adds. “With this technique, it might be possible to burn real grayscale pictures in different materials like wood, paper, etc.”
Intrigued? You can see it in action below, as well as find the code on GitHub.