Project Details: The following project details will include the following subjects: • Project Description • Mechanical Details • Code specifications (libraries and dependencies etc.) • Generating G-code Project description: • The project is a mini CNC machine or a X-Y plotter, that moves along three axes to draw any image uploaded onto it. Mechanical Details: • Two stepper motors from scrap DVD-ROMS are used to move along the x and y axis. A servo motor with a pen attached to it controls the z motion, that is the up-down motion of the pen. • L293d motor shield along with the Arduino UNO is used as the motor controller. • The shield provides control for two stepper motors and two servo motors. • Wires are to be soldered on the steppers. For each stepper two wire pairs should show continuity. • Heat sinks can be attached for better performance.
Code Specifications: There are two parts: 1) the Arduino’s firmware 2) The processing Code for communicating with the serial monitor. Firmware for Arduino: • The code can be accessed from: https://github.com/Tahoor27/3-Axis-mini-CNC-machine • The respective library corresponding to the motor driver is to be used. In case of the l293d motor shield the ADAFRUIT – motor shield library is used, it can be downloaded from: https://learn.adafruit.com/adafruit-motor-shield/library-install • Info for stepper class is given here: https://learn.adafruit.com/afmotor-library-reference/af-stepper-class • Motor speeds / efficiency can vary, therefore introducing a step delay or a line delay can improve results. Processing: • Processing IDE would be used to communicate the g-code with the Arduino’s serial monitor. • It can be downloaded from (download any version above 3): https://processing.org/download/ • The GCTRL code can be accessed from: https://github.com/Tahoor27/3-Axis-mini-CNC-machine • For more info: https://www.instructables.com/id/How-to-Make-Mini-CNC-2D-Plotter-Using-Scrap-DVD-Dr/
Generating G-Code: • G-code can be generated from an open source software called ‘Inkscape’. It can be downloaded from: https://inkscape.org/release/inkscape-0.92.4/ • Download the g-code extension for Inkscape from: https://github.com/martymcguire/inkscape-unicorn/ • The Document properties for Inkscape are to be changed to: (80 x 80) mm • The images should have width and height of (40 x 40) mm • Before saving the image as g-code, the bit map of the image is to be created. • For more info: https://www.youtube.com/watch?v=GmcmdVhCqu4