Flsun Super Racer - Capybara Toolhead Project with Bambu X1C Hotend UPDATED

Basic Information:

New update available!!!

This project is a modification of the toolhead for the Flsun Super Racer, based on the Bambu X1E hotend. It is a remix of several existing projects:

• Extruder: uToolhead by VICLER

• Effector Plate: by Werebear93

• Bambu Hotend: by Nanodesigner

• Fan 5015: by DeltaDesignRus

• Fan 2510: by PXP11

Important Assembly Notes:

• Effector Plate Modification: This project requires modifying the Effector Plate by drilling, filing, or milling a hole. After this modification, the plate will no longer be compatible with standard configurations. I recommend purchasing an extra plate for testing from AliExpress: Link.

• Cooling System: I use Gdstime 5015 24V 8500RPM fans in my printer. If you plan to use weaker fans, I recommend the "fanduckt_asymmetric_flow" version for better airflow.

• I have replaced the 2510 fan with a Sunon 12V version

Recommended Print Parameters:

Layer height: 0.12-0.16mm

Parts List:

PLA:

• distance_hotend_base x1

• Fan_adapter x2 (second mirrored)

• Fan_stabilizer x1

ABS:

• fanduckt_wide x1 / fanduckt_asymmetric_flow x1

• hotend_mounting_base x1

• uToolhead_remix_extruder_back x1

• uToolhead_remix_extruder_body_&PTFE_connector x1

PETG:

• probe_sensor_holder x1

• uToolhead_remix_extruder_lever x1

uToolhead Extruder Modifications:

• Short PTFE tube: needs to be cut at trapezoid-shaped tip from the bottom of extruder

• Added PTFE tube holder (glue-mounted).

• Thicker filament tension lever.

• Filament inlet: 1.2mm – should be manually drilled to 2-3mm.

• Filament outlet: 3.8mm – should be manually drilled to 4mm.

• Tension spring: I use a weaker and shorter spring than the stock BMG version.

• PTFE tube fitting: Instead of the standard one, I use a fitting from Orbiter 2.0.

Klipper Extruder Configuration:

[extruder]
step_pin: PD6
dir_pin: PD3
enable_pin: !PB3
microsteps: 16
full_steps_per_rotation: 200
rotation_distance: 4.516
nozzle_diameter: 0.4
filament_diameter: 1.750
max_extrude_only_velocity: 120.0
max_extrude_only_distance: 100.0
max_extrude_only_accel: 2000.0
heater_pin: PE5
sensor_type: Generic 3950 
sensor_pin: PC1
min_temp: -5
max_temp: 300
smooth_time: 2.0

Design Details

Hotend Mounting Base:

• Holes are undersized to prevent heat inserts from melting – use hot screw threading.

• Front mount for ADXL345 sensor – a cheap one from online stores (no specific source available).

Fan Adapter:

Warning! The installation is tricky and requires short M3 screws (about 4-5mm). Installation order:

1. First, attach the adapters to the Effector Plate.

2. Then mount the 5015 fans.

Summary:

I'm sharing this project because I've been meaning to for months. The toolhead works well, and I don't plan on making further changes. Updates might come in the future.

Currently, I'm working on an active air filtration system and implementing The Pico MMU.

HF! 😊

UPDATE 19.05.2026:
The new version includes updates to:

• extruder holder - Improved stability where it rests on the effector plate,

• part cooling fans - Moved upwards to allow quick and easy access to the extruder gears,

• new probe with a dedicated holder,

• fanducts - Redesigned for way more efficient airflow and cooling.

All new parts are in "New version" folder.