Merlins Qidi-X-Plus X-Max Printhead-Mod

This is a modification for the qidi x-plus / x-max printer.
It fits on the original carriage (02.2022) and works within normal limits because the nozzle position is almost the same as the original. It works with all previously used fan-ducts.

This mod is made to get nicer printing results without too much hassle and with the ability to switch back to the original print head in just a few minutes. It is specially designed for phaetus dragon (i use the standard version) and LDO Orbiter V2.

Here you can see the the first-Version printing

Building this printhead requires a bit of experience (how to crimp, how to use inserts, and so on), so it's probably not for absolute beginners.

Whoever uses this modification should know what he is doing, and does it on his own responsibility.

A special fan duct for ABS is still under development and will be presented at a later date.

And last but not least big thanks for the inspirations from humebeam and the information from olaf (https://www.elektrifiziert.net/) and humebean. Their fantastic work has encouraged me to try around a bit myself. 

Overview

1 Mainframe 2 Dragon-bracket 3 Extruder-bridge 4 fan-duct-adapter     (for original fan-ducts) 5 Ribbon-cable-holder 6 Partfan 24V 7 LDO Orbiter V2 8 Qidi PCB 9 Hotend-Fan 10 Qidi Carrier 11 Phaetus Dragon standard

Used electric Main-Parts 

• phaetus dragon standard
   
• LDO Orbiter V2
   
• SUNON MF40202V2-1000U-A99 40x40x20mm 24V Fan
   
• WINSINN 5015 (FAN5015G24D) Partfan 24V 2,4W  
  50x15mm - 16,28mmH₂O - 3,23 CFM

         also requires a 40 watt heating cartridge and a type K thermocouple, both for 24V:

• K-Type Thermocouple (up to 500°C) 3x15mm:   
  https://de.aliexpress.com/item/32835036293.html
   
• 40 watt heating cartridge 6x20 mm:  
  https://de.aliexpress.com/item/32815934251.html
   

Fasteners used 

Print

I printed this mod with Fillamentum ABS.  So far I used it for about 9 months to print ABS and ASA up to 250°. If you want to print at higher temperatures, I recommend printing at least the lower parts in polycarbonate blends (e.g. Prusa PC Blend Carbon Fiber) or other materials with higher temperature resistance.

Printed with fillamentum ABS 0.2mm layer height, for the ribbon-cable holder i used a brim.

placement & support

placement for no-support parts	support touch build-plate
main part, printed with support=off plus one custom support box 10x25x21 mm

Preparation (inserts/wiring)

M3 inserts should be used in all 4mm holes (ruthex style inserts are recommended).

If inserts with outer diameters other than Ruthex are used, e.g. Voron-Style inserts, you can extend the diameter of the 4 mm holes to 4.5 mm using a drill bit.

Some holes are made for possible extensions.

Please note the colors of the wires (extruder and so on).

Assembly

Note: The adjustable ribbon cable holder (5) is fitted with an M3 insert from below. The distance pieces (3) and (4) has different length because there is a difference in the qidi carrier. The screws for (1) are included in the phaetus package.

                      Do not forgot the PTFE-Inliner.

Installation

Install merlins-printhead-mod:

1 - Just to be on the safe side, use the Fast-Level Position to set the bed to a about 1mm lower position
2 - Unload the filament and disasemble the original printhead
3 - Assemble the new printhead
4 - Run (print) the script "Set-XPlus-to-Merlins-Printhead.gcode"
5 - Check the directions of printhead and extruder
6 - perform a fast-leveling
7 - done.

Install the original printhead:

1 - Just to be on the safe side, use the Fast-Level Position to set the bed to a about 1mm lower position
2 - Unload the filament and disasemble the merlins-printhead-mod
3 - Assemble the original printhead
4 - Run (print) the script "Set-XPlus-to-QIDIs-Printheads.gcode"
5 - Check the directions of printhead and extruder
6 - perform a fast-leveling
7 - done.

Set-XPlus-to-Merlins-Printhead.gcode  (it works also for x-max without any modification)

; Merlin-Mod V1.0 
; FOR QIDI X-Plus PRINTERS
; BY Merlin64

; Sets QIDI X-Plus Configuration to use with the Merlins Printhead
; testet with an early 2022 Modell

M8005 I1; Drehrichtung Extruder Motor
M8011 S0.001570796; E-step adjustment
M8500; Save changes

Set-XPlus-to-QIDIs-Printheads.gcode (it works also for x-max without any modification)

; Merlin-Mod V1.0 
; FOR QIDI X-Plus PRINTERS
; BY Merlin64

; Sets QIDI X-Plus Configuration to use with the original Printheads
; testet with an early 2022 Modell

M8005 I-1; Stepper motor direction
M8011 S0.010484; E-step adjustments with optimized E-steps, use S0.0107 for the default qidi setting
M8500; Save changes

With some qidi-firmware versions there are problems with the loading process after the unloading process (wrong extruder rotation direction).

To avoid resets you can run (print) this script to unload the filament from the preheated hotend instead the original unload procedure. 

; Unload-Filament-Script
; FOR QIDI X-Plus / X-Max with Orbiter II
; Code example from youtube 
; "Orbiter Extruder simple filament load and unload procedure"

; Filament aus dem Orbiter entladen

G0 E-5 F3600   ; filament aus Heizblock hochziehen in kalten Bereich 
G4 S3          ; wait for three seconds
G0 E5 F3600    ; filament 5mm in Heizblock zuruecksch. (stringing vermeiden)
G0 E-15 F3600  ; filament m. 3600 mm/min in kalten Bereich zurueckziehen 
G0 E-80 F300   ; die Filamententnahme langsam fortsetzen, 
; damit das filament kalt ist, wenn es die Zahnraeder erreicht