Ender Multi Material Upgrade (eMMU) (WIP)

eMMU (ender Multi Material Upgrade)

Use four Creality Sprite Extruders to create yet another MMU.  Heavily inspired by Prusa's MMU1 and Bambu's AMS Lite. We can argue they are both basically the same concept, a filament multiplexor. Hence the use of both of them here.

This mod is compatible with both Klipper and Marlin. You can technically make it work with more than 4 colors as well with some extra tinkering.

I've been running this mod for a few months, and it is working just fine. Still have some plans on adding a filament cutter in the future but so far, it's ready for release.

Will be updating this model as time goes with everything to get it started. Stay tuned.

Hardware

BOM

Controller

You have two options, depending on which firmware you are running.

Marlin

If you are using Marlin firmware, you can utilize a stepper motor multiplexer. For that you have either commission a PCB made for you (JLCPCB, PCBWay), or you can hand-wire it yourself using the schematic (DIY). 

The schematics and gerber files are available here: 

amd989/MMU_Stepper_switch: MMU1 Multiplexer stepper switch. Easy MMU for any marlin enabled 3D printer

This is a modified version of the Prusa MMU1 multiplexer intended for easier soldering (no surface mount components)

Klipper

For Klipper we require to use a secondary 3D printer board instead of a multiplexer. With a second board, you can configure your Klipper host to control both boards (aka MCU) at the same time. Allowing you to extend control of the extra four extruders without any intermediaries.

With this sorted, we can take advantage of the awesome project Happy-Hare for easy multi-material printing with Klipper

Configuration

Marlin

Your board has to have at least 2 GPIOs free (3 for 5-8 Extruders)

src/pins/<cpu>/pins_<board>.h

Define the extra extruders the default is 4, this is what I did for my SKR v3 mini:

#define E0_ENABLE_PIN                       PD1
#define E0_STEP_PIN                         PB3
#define E0_DIR_PIN                          PB4

// MMU
#define E1_ENABLE_PIN                       PD1
#define E1_STEP_PIN                         PB3
#define E1_DIR_PIN                          PB4

#define E2_ENABLE_PIN                       PD1
#define E2_STEP_PIN                         PB3
#define E2_DIR_PIN                          PB4

#define E3_ENABLE_PIN                       PD1
#define E3_STEP_PIN                         PB3
#define E3_DIR_PIN                          PB4

Configuration.h

#define EXTRUDERS 4

#define SINGLENOZZLE

#define MMU_MODEL PRUSA_MMU1

Configuration_adv.h  (Optional/Advanced)

If you are going to use more than 4 extruders

  #define E_MUX2_PIN IO3  // Needed for 5 to 8 inputs

Klipper

Coming soon...