Prusa MK3 Octoprint lit-nozzle and switch, Revised and Improved version R4, including extruder cover REV4

myminifactory

This project started out to conserve power by illuminating my MK3 Octopi fitted 3D printer during nighttime printing sessions. The modified nozzle features two TO1 bright white LEDs and two 100 Ohm resistors, while the nozzle fan holder was transformed into a mini rocker switch holder. Power is drawn from the Noctua fan's GND and 5V lines, so lighting is automatically enabled when the nozzle heats up. This can be disabled by flipping the mini rocker switch or when the Noctua fan shuts off after printing. The parts were created using PETG material and printed on my MK3. Four significant improvements have been made to simplify printing, assembly, and ensure a better fit onto the extruder cover in the revised version. The LED holder is now a single piece that combines the nozzle and holder, bridging where the switch is located and integrating the wiring. Only two leads (5V PWR & GND) exit on the side and need to be connected safely to the Noctua fan or another 5V source if desired. I noticed no performance degradation when connecting to the Noctua fan! Attachment to the extruder cover is achieved through three points (two M3X10 and an additional M3x8 with square nut placed in the right corner of the R4 modified extruder cover). The system securely holds the angled cooling fan as depicted. Prints were prototyped using OpenSCAD, importing existing MK3 designs and produced on my MK3 units, using Orange and Black Prusa PETG as well as transparent Blue PETG. These prints were created without support, utilizing a 0.4mm standard nozzle and Prusa PETG Slic3r defaults with 20% fill and 0.2mm layer thickness. This brings me to the fourth and final improvement visible on both the modified extruder cover R4 and the modified nozzle fan holder R4: a recycling PET logo is imprinted, aiming to facilitate end-of-life recycling of the printed part. I encourage everyone to include this feature on prototyped parts to contribute to a greener planet footprint moving forward! Note that this assembly has reduced the number of parts from three to two and ensured better mounting and rigidity. The weight difference is minimal: 276 vs 220 in the existing MK3 version. I hope you'll enjoy the impact when monitoring your MK3 with Octoprint camera during nighttime hours, even in less well-lit areas. Enjoy!