Geeetech A20M / A10M NF Crazy TC-03 hotend mount & Fan Duct

thingiverse

This is a design to attach the NF Crazy TC-03 2in1 hotend to my Geeetech A20M printer. I made a first design that did not fully meet my expectations. Then, I created a second one (files with "flat" in the names) which has several advantages over the initial one: * The bed is now 250mmx250mm instead of 250mmx240mm. * Better nozzle visibility. * The BL touch is 8mm closer to the nozzle. * A better-placed fan duct optimizes wipe tower space, avoiding collision with the printer head ("No sparse layers" option in Prusa slicer). * The best spot for the wipe tower to optimize bed surface is the upper right corner. Note: In the second design, the 30mm hotend blower is located at the back. This hot-end combined with a pair of BMC extruder gives me significantly better results than the original A20M hot-end. For example, retraction length is only 1.8mm and I do not have any stringing problems whatsoever. Note: This hot-end is a 2in1 hotend so you lose the mixing capacity. To update your printer, you will need: * NF Crazy TC-03 hotend (available on aliexpress). * 24V 5015 blower. * BL Touch. * 3mm bolts and nuts of various lengths. * Electrical connectors. After attaching the hotend, some adjustments have to be made in firmware: Marlin firmware Update for 1st design: #define TEMP_SENSOR_0 5 #define TEMP_SENSOR_1 5 #define Y_BED_SIZE 240 #define NOZZLE_TO_PROBE_OFFSET {29, 0, 0} #define Y_MIN_POS 0 //#define MIXING_EXTRUDER #define BANG_MAX 200 Marlin firmware Update for 2nd design (flat): #define TEMP_SENSOR_0 5 #define TEMP_SENSOR_1 5 #define NOZZLE_TO_PROBE_OFFSET {-21, 0, 0} //#define MIXING_EXTRUDER #define BANG_MAX 200 A few weeks later, I decided to switch to Klipper firmware. My A20M Klipper profile is attached. Printer configurations: 1st design: printer_design_v1.cfg 2nd design: printer_design_flat.cfg Slicer Configuration: I use Prusa Slicer with its unique multi-extruder features MMU. You can see my Prusa Slicer multi-extruder configuration in the pictures. My Prusa Slicer 2.2 config file is attached. Video: https://youtu.be/Zpohu0GCE4Y 20/12/2020: New configuration resolves some random clogging and significantly speeds up filament change. * Update pictures with filament settings and extruder settings. * Update Prusa_silcer.ini.