Bowden dual/quad extrusion extruder (single-nozzle single-drive) for MG995 SERVO

thingiverse

I'm including this remix body that accepts an MG995 Servo, which is much cheaper than the original design's Servos and has more torque. This remix also uses two M4 screws to hold the extruder in a 2020 openbuilds frame. UPDATED: I've added a new idler that's much stronger, using two M3 nuts for the spring screws and one nut for the bearing. This new design makes the construction stronger to hold the screws in place. NEW body V3 is easier to tighten PC4-M5 fittings and smaller than the first version. To use 2 steppers and 4 filaments in MARLIN RC8, just change these files from the original thing on Thingiverse: https://www.thingiverse.com/thing:1643906 Configuration.h should be changed to: #define SINGLENOZZLE #if ENABLED(SINGLENOZZLE) #define SINGLESWITCH_EXTRUDER_SERVO_NR { 0, 1 } // Servo 0 for E0, E1, servo 1 for E2, E3 #define SINGLESWITCH_EXTRUDER_SERVO_DELAY 700 #define SINGLESWITCH_EXTRUDER_SERVO_ANGLES { 150, 30, 150, 30 } // Angles for E0, E1, E2, E3 #endif Also define SERVOS for your board: #define NUM_SERVOS 4 // MKS Gen 1.4 supports 4 servos Marlin_main.cpp should be changed to: #if ENABLED(SINGLENOZZLE) inline void move_extruder_servo(uint8_t e) { const int angles[4] = SINGLESWITCH_EXTRUDER_SERVO_ANGLES; const int servo_nr[2] = SINGLESWITCH_EXTRUDER_SERVO_NR; MOVE_SERVO(servo_nr[e/2], angles[e]); delay(SINGLESWITCH_EXTRUDER_SERVO_DELAY); servo[servo_nr[e/2]].detach(); } #endif #if ENABLED(SINGLENOZZLE) stepper.synchronize(); // if using MARLIN RC8 // planner.synchronize(); // if using MARLIN bugfix build 1.1.x uncomment this and comment the line above move_extruder_servo(tmp_extruder); #endif In your BOARD.h file, create E2 and E3 pins using the same pin definitions used for E1 pins, change all E1 pins to be the same as E0 pins. This way E0 and E1 will use the first stepper motor, and E2 and E3 will use the second stepper motor.