Dual E3D Extruder with servo

thingiverse

I have made a few minor design tweaks that are purely cosmetic, so the images may look slightly different from the STL files. I previously created a couple of dual extruder versions for the Creality CR-10, but there's always room for improvement. This time around, my goal was to eliminate the tedious alignment process required for the Z height of the second extruder, ensuring its nozzles don't scrape into previously laid layers. To achieve this, I incorporated a servo that lifts the secondary extruder. The cooling duct is designed to blow air from two directions, providing even cooling. A THX900-sized servo is used, mounted with an eccentric on the shaft. Mount it at its highest point when the extruder is raised, eliminating the need for continuous power supply since the springs won't be able to move it in that position. Two M3 holes or a similar size must be drilled and tapped into the printer's mounting plate. Alternatively, one can use screws and nuts if tapping isn't feasible. Two standard springs are used to push the extruder carrier downwards; finding suitable ones shouldn't be challenging. For the BLTouch bracket, an M3 nut is utilized, while an M4 nut is used for the part fan. These are not standard types but rather inserts melted into the holes with a soldering iron, as shown in the example picture. The metal sliders that the extruder carrier glides on have a diameter of 3 mm. It's essential to print this component in HIPS or a similar material that's more heat-resistant than PLA. I've tested it with PLA, and while it works initially, it deforms and becomes brittle over time. Additionally, the cooling duct was designed for my clone E3Ds, so its height might be incorrect. A variant of the file is available where you can cut off excess throat height before gluing it to the fan. This version should accommodate most E3Ds. In Marlin, modifications need to be made in the config file: // //#define SWITCHING_NOZZLE //#if ENABLED(SWITCHING_NOZZLE) //#define SWITCHING_NOZZLE_SERVO_NR 1 (0 or 1 based on the number of servos you have; I have a BLTouch Probe that functions as a servo, and that's servo 0 for me) //#define SWITCHING_NOZZLE_SERVO_ANGLES { 90, 0 } // Angles for E0, E1 //#define HOTEND_OFFSET_Z { 0.0, 2.0 } (the offset must be measured after installation and is set as -2 here as an example) //#endif //#define NUM_SERVOS 2 (Total number of servos including BLTouch probe if present) //#define SERVO_DELAY { 0, 300 } (delay for both servos, with a delay of 0 for my BLTouch and 300 for the extruder servo) //#define DEACTIVATE_SERVOS_AFTER_MOVE