OpenBuilds MiniMill - Triple Threat Conversion

thingiverse

OpenBuilds approached me to turn a standard MiniMill into a 3D Printer. They provided a full kit, three Nema 23 stepper motors, a 24V Meanwell power supply with the OB Power Case kit, an OB wiring kit and three limit switch kits. They also supplied a Duet 2 WiFi in their OpenCase mounting system and a 24V E3D Titan Aero kit. I quickly realized that the standard MiniMill kit was not suitable for a 3D printer due to its limited Z height. However, it could make an excellent small laser engraver. That's why I added a laser engraver head to the conversion - making this a 3-in-1 conversion, which we call the Triple Threat! The L-Cheapo 10 watt laser diode I added can run off of either 12V or 24V supply and has enough power to cut and engrave most wood, acrylic (except clear) and etch on anodized aluminum. You can use the STL files attached to reproduce the 3D printer conversion mounts and the laser engraver conversion mount. The mill/router portion would still require a normal spindle or handheld style router. The Duet RepRap firmware is capable of handling all three modes of operation and each mode can be called using g-code. The one thing that the Duet 2 WiFi requires to work properly with PWM laser control is a signal inverter. A link to the circuit hardware required is on the Duet Wiki [here](https://duet3d.dozuki.com/Wiki/Laser_PWM_control). I opted to have a prototype board produced by OSHPark and soldered it up myself. It plugs directly into the Duet 2 WiFi and only requires 24V power input and output wires to the laser diode control board. You can read more about the project on the OpenBuilds build website [here](https://openbuilds.com/builds/live-openbuilds-minimill-miniprint-laser-conversion-demo-mrrf2019.8288/).