Creating Bespoke Engineering Projects
Neil Devonshire
This CNC Mill conversion was started to speed up my MGF electric vehicle conversion project, where I realised fairly early on that it would take nearly 2 years to complete if I machined all parts manually. Now, it's a full project in its own right. This Mill is controlled only by an Arduino based Teensy 4.1 microcontroller and sends movement commands to Brushless DC Motors via the ODrive precision motor controller. It now runs G-Code from Fusion 360 directly from an SD card.
LCD Display for CNC
It's all well and good having a CNC machine, but wouldn't it be better to see all the details on an LCD display or 2?
In this video, I assemble, program and test an LCD display module using a Pololu Mini Maestro 24 channel Servo controller (with a little festive message). I intend to display position information for the X, Y and Z axes (in mm) and spindle speed on one display, then program information on the other. Such as current GCode commands, ODrive state, etc.
Setting up a Brushless Motor
Most home CNC setups use Stepper motors to control the movement of the X, Y and Z axes, although as their speed increases the Torque drops off dramatically. So I opted for BLDC motors (BrushLess DC).
BLDC motors retain their Torque throughout the speed range and with the help of an ODrive speed controller can maintain high position holding forces. These are ideal for CNC control.
Also, the ODrive uses Closed-Loop Control so the position is accurately maintained, unlike many stepper motor drivers that rely on counting steps applied to the stepper motor, with no feedback of position accuracy.
