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

thingiverse

This remix will accept a MG995 Servo, this is only the body, the other pieces you can print from original thing. This Servo is MUCH MUCH more cheaper than the ones used in original design (and have more torque also). Also I'm including changes to make a QUAD extrusion in Marlin RC8 (tested and working !!!). This remix also uses two M4 screws to hold the extruder in the 2020 openbuilds frame. UPDATED: Added a NEW idler MUCH STRONGER, this new idler uses two (2) M3 nuts for the spring screws, and one (1) nut for the bearing. This new design makes the construction more stronger to hold the screws in the idler. For the spring screw you should use a top washer and nut to tighten the screw in place. UPDATED: New body V3 makes easy to tight the PC4-M5 fittings, and it's smaller than the first version. Changes in MARLIN RC8 to use 2 steppers and 4 filaments. Just change the original files from the thing https://www.thingiverse.com/thing:1643906: Configuration.h (change to): <pre><code> #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 </code></pre> Also make sure you define the SERVOS for your board: <pre><code> #define NUM_SERVOS 4 // MKS Gen 1.4 supports 4 servos </code></pre> Marlin_main.cpp (change to): <pre><code> #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 </code></pre> <pre><code> #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 </code></pre> In your BOARD.h file (eg. in my case MKS GEN 1.4: pins_RAMPS.h): 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 be using first stepper motor, and E2 and E3 will be using the second stepper motor (in my Case MKS GEN 1.4 there's only two extruders motors, if yours have 3 (like RUMBA) you can even make change all the files above to have a HEXA filament extrusion. I have a rumba but I can't use this thing since I use with it a Diamond Hotend. This works very nice, I have tested it. Just need to change the tool change script, and believe me, Simplify3D is the best way to deal with this tool change script