FlyingBear Ghost 6

This 3D printer is an affordable Core XY option. I documented my assembly steps with additional information to supplement the manual, this may help those looking to make upgrades.

Sections

• Motherboard
  • Firmware
  • PID tune
• Hot-end
• Z Stop
• PTFE Tube
• Upgrades
  • Klipper

Nathan Builds Robots posted a review of this machine, including some upgrades to the power connections and heat-break. I used this as a springboard of items to check when assembling my own Ghost 6.

Motherboard

As of March 2023 FlyingBear appear to ship the Ghost 6 with fork connectors on the power cables, a welcome change from tinned wires as seen in NBR's review.

The motherboard is a Makerbase Robin V3.1 (OEM Nano4 variant?) with four soldered stepper drivers and a socket to install an additional driver. The processor is a 32-bit single-core STM32F407VET6 running at 168Mhz.

This board ships running Marlin 2.x but also supports RepRapFirmware (RRF) and Klipper. Firmware images are available from the Makerbase Nano V3 Github repository.

The electronics bay, the noisiest component is the 60mm fan cooling the motherboard. The PSU fan is temperature controlled and only runs when needed.

It's encouraging to see the frame has been grounded with a 16AWG earth wire (bottom left).

This is a low profile 6010 fan. The noise it emits is exacerbated by it's close proximity to the metal side panel.

Ghost 6 wiring diagram (PDF), provided by FlyingBear:

A closer look at the MKS Nano4 V3.1 wiring:

Stock firmware

Connecting to the printer via serial console over USB allows us to retrieve the firmware settings. I used Pronterface as a serial terminal client.

M115

FIRMWARE_NAME:Marlin 2.0.9.2 (Nov 11 2022 12:40:55)
SOURCE_CODE_URL:github.com/MarlinFirmware/Marlin
PROTOCOL_VERSION:1.0
MACHINE_TYPE:3D Printer
EXTRUDER_COUNT:1
UUID:xxxx-xxxx-xxxx-xxxx-xxxx
Cap:SERIAL_XON_XOFF:0
Cap:BINARY_FILE_TRANSFER:0
Cap:EEPROM:1
Cap:VOLUMETRIC:1
Cap:AUTOREPORT_POS:0
Cap:AUTOREPORT_TEMP:1
Cap:PROGRESS:0
Cap:PRINT_JOB:1
Cap:AUTOLEVEL:0
Cap:RUNOUT:0
Cap:Z_PROBE:0
Cap:LEVELING_DATA:0
Cap:BUILD_PERCENT:0
Cap:SOFTWARE_POWER:0
Cap:TOGGLE_LIGHTS:0
Cap:CASE_LIGHT_BRIGHTNESS:0
Cap:EMERGENCY_PARSER:0
Cap:HOST_ACTION_COMMANDS:0
Cap:PROMPT_SUPPORT:0
Cap:SDCARD:1
Cap:REPEAT:0
Cap:SD_WRITE:1
Cap:AUTOREPORT_SD_STATUS:0
Cap:LONG_FILENAME:0
Cap:THERMAL_PROTECTION:1
Cap:MOTION_MODES:0
Cap:ARCS:1
Cap:BABYSTEPPING:1
Cap:CHAMBER_TEMPERATURE:0
Cap:COOLER_TEMPERATURE:0
Cap:MEATPACK:0

M503

echo:; Linear Units:
  G21 ; (mm)
echo:; Temperature Units:
echo:  M149 C ; Units in Celsius
echo:; Filament settings (Disabled):
echo:  M200 S0 D1.75
echo:; Steps per unit:
echo:  M92 X160.60 Y160.60 Z800.00 E405.00
echo:; Max feedrates (units/s):
echo:  M203 X200.00 Y200.00 Z4.00 E45.00
echo:; Max Acceleration (units/s2):
echo:  M201 X1500.00 Y1500.00 Z100.00 E2000.00
echo:; Acceleration (units/s2) (P<print-accel> R<retract-accel> T<travel-accel>):
echo:  M204 P1500.00 R3000.00 T2000.00
echo:; Advanced (B<min_segment_time_us> S<min_feedrate> T<min_travel_feedrate> X<max_x_jerk> Y<max_y_jerk> Z<max_z_jerk> E<max_e_jerk>):
echo:  M205 B20000.00 S0.00 T0.00 X15.00 Y15.00 Z0.40 E2.00
echo:; Home offset:
echo:  M206 X0.00 Y0.00 Z0.00
echo:; Hotend PID:
echo:  M301 P11.58 I0.61 D55.36
echo:; Bed PID:
echo:echo:  M304 P103.73 I17.06 D420.46
echo:; Power-loss recovery:
echo:  M413 S1 ; ON

I was not able to read or set the driver current with M906 (Marlin docs), most likely because the MKS Nano4 board uses TMC-2225 stepper drivers that aren't supported. The stock firmware returns 'Unknown command'.

PID Tune

While I had a serial console session active, I took the opportunity to PID tune the hot-end and bed.

• Hot-end (200C):
  M303 E0 S200 C6 U1
• Bed (60C):
  M303 E-1 S60 C8 U1
• Save to EEPROM:
  M500

I encountered some errors after PID tuning using U1 but the PID values had updated and just required saving (M500).

Hot-end

I disassembled the hot-end enclosure to inspect the heat sink and heat-break dimensions. This printer has a PTFE lined hot-end that runs down to the nozzle. As with other printers like the Ender 3, this limits the print temperatures to 240C as above this the PTFE tube burns.

I have tested the stock extruder and hot-end flow rate performance.

The heat-break can be swapped out. It is a Chimera style, M6 threaded bottom that screws into the heater block and a smooth J-head M7 throat that inserts into the cold-end heat sink (Aokin sell a cheaper bi-metal TA-C smooth short variant).

The heat sink attachment in the yellow plastic hot-end enclosure appears bespoke. If you purchase an aftermarket alternative, you may need to drill and tap some M3 holes in the top of the heat sink near the perimeter to install it.

Z Stop

I found my Z stop micro-switch was not level from factory. This was easily remedied as it is mounted on a plate fixed with two bolts (circled in red), screwed into the rear panel of the frame.

The Z stop plate bolts can be loosened from the rear of the machine.

PTFE Tube

When installing the PTFE tube from the frame edge to the extruder I checked the tube dimensions versus some Capricorn and Creality ender 3 tubing. The factory tubing appears to match Capricorn inner and outer dimensions.

This printer has a direct drive extruder, slack in tube's filament path before reaching the extruder does not affect print quality versus Bowden configurations where the PTFE tube sits between the extruder and hot-end.

Slicer settings

I use Cura 5 to slice models. There is no Ghost 6 profile (at the time of writing) so I selected Ghost 5 and modified the print bed size and Z height (255 x 215 x 215 XYZ).

Notable changes to date (PLA):

• Retraction distance: 0.3mm (down from 6.5mm)
• Minimum extrusion distance: 1mm (down from 10mm)

Not a slicer setting but a Marlin change, disable power loss recovery that writes to the SD card at every layer, causing pauses during printing: M413 S0

Upgrades

Relocate the Power Supply

To create space in the electronics compartment, the PSU can be relocated to the underside of the printer. This requires taller feet, those TPU feet shown below are temporary. I plan to print a voron style skirt for my Ghost 6 and raise the printer by 60~70mm.

Without modification the bottom clearance is 19mm.

The Ghost 6 ships with four holes in the bottom plate, these can accommodate M6 bolts allowing DIN rails to be attached. I installed mine across the underside. This allows components to be installed without adhesives or cutting holes in the original frame. The picture below shows the left hand side of the Ghost 6, with the door facing to the right.

Initially I installed two DIN rails. Only the power supply needed relocating, the remaining components can live in the electronics compartment.

I happened to have a spare Meanwell LRS 350 PSU, from a previous printer, that I'd modified with a 90mm noctua fan for near silent operation.

Klipper

Having moved my power supply to the underside of the printer, I could then accommodate a single board computer to host klipper. I have posted my Ghost 6 klipper configuration for others to use. Please run your own PID, retraction and pressure advance calibration.

Robin Nano 4 make menuconfig settings if using UART pins for RX/TX communication:

To flash your Robin Nano board with klipper, follow the klipper installation instructions. After producing a .bin file, rename it from klipper.bin to robin_nano_4.bin. Place the bin file on an SD card and power up your Ghost 6.

Bi-metal heat break and hardened nozzle

The original hot-end assembly weighs 39g, the lower X carriage weighs 97.7g, totalling ~137g not including the extruder (that probably weighs more) and top assembly housing the linear bearings.

The hot-end assembly

Lower X carriage that houses a break out board, fans and the hot-end assembly

I'll need to retain the cold-end heat sink, the top is attached via custom placed M3 threaded holes instead of a J-head like many V6 hot-end printers.

My TriangleLabs CHC hot-end with nozzle weighs 20g. This upgrade will save a negligible 3g (36g vs 39g), allow print temperatures above 240C without burning the PTFE tube and be able to print abrasive materials without wearing the nozzle.

Acrylic side panels

Not a print quality upgrade but a quality of life one. I opted for light smoke acrylic side panels to increase the light inside the printer and to provide an easier view of print progress.

As you can see from the photo, my panels are perhaps 1mm too narrow. If ordering your own, I recommend 342 x 315mm sized sheets. I drilled M3 (3.5mm drill) holes and attached using pre-existing mount points.

Tip: to position your drill points, remove your metal side panels and lay your acrylic on it to mark the hole locations.

Next

I have some other modifications planned. I'll update these notes in due course but am happy with the quality of the hardware, particularly at this price point.

Useful Ghost 6 repositories

• Tom Tomich's Ghost 6 repository (Russian)
• Technarrus klipper config (Orange Pi 3 LTS) (Russian)