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Achieve Worry-Free Printing: A Deep Dive into the Mellow LLL Flux Buffer Auto-Refill System
By 3Dmellow TeamSeptember 16th, 2026132 views
Tired of failed prints? The Mellow FLY LLL Flux Buffer offers seamless auto-reloading and tangle detection. Upgrade your 3D printing workflow with this smart filament management solution.
For every 3D printing enthusiast, no matter what printer you own, running out of filament is a universal headache.
Does your favorite long-term print get ruined just because your single spool ran dry unexpectedly?
Are you tired of constantly babysitting your machine, anxious about missing the swap window during those crucial overnight prints—regardless of your setup? 💔
This is exactly why the Mellow LLL Flux Buffer was created. It is not just a simple filament refiller; it is a premium auto-reloading and filament management system designed specifically for FDM 3D printers. It perfectly solves downtime issues caused by filament runouts and tangling, allowing you to say goodbye to manual interventions and embrace a worry-free creation experience! 🚀
🎥 Video Demo: How does it work?
🔍 Why choose the LLL Flux Buffer?
This device is far more than just a "dual spool holder"; it integrates an innovative mechanical cutting mechanism, smart electronics, and intuitive physical controls into a complete solution.
Seamless Auto-Reload & Dual Spool Mounting The system supports mounting two spools directly, or connecting to a filament Dry Box to maintain optimal material condition. When the primary spool runs out, it automatically and seamlessly switches to the backup spool without pausing the machine or requiring manual intervention, significantly reducing operator attendance costs.
Powered Cutting (No External Power Needed) This is a brilliantly clever design! It features a purely mechanical cutting mechanism driven purely by Extruder Traction. This means no extra wiring or motors are needed to control the cutter, ensuring reliable auto-cutting while simplifying installation.
Tangle & Runout Detection (Double Safety)
Anti-Tangle: Equipped with a dedicated metal anti-tangle cutter. If a tangle, jam, or empty spool is detected (indicated by a red light), it automatically cuts the filament to prevent knots.
Buzzer Alarm: If both spools run out, the built-in Buzzer provides an audible alarm to remind you.
Motor Channel Sensors (S1/S2): Each motor channel includes two sensors, detecting the filament "entering the channel" and "reaching the motor exit" respectively.
Buffer Sensors (B1-B4): The buffer contains 4 position sensors that precisely control feeding, stopping, retracting, and channel switching.
B1: Detects if there is filament in the buffer path.
B2: Forward position, triggers feeding.
B3: Stop position, triggers stopping the feed.
B4: Retract position, triggers retraction.
Intuitive 5-Button Control Panel Don't want to rely on software? No problem. The device features independent Load and Unload buttons for both the left and right spools, plus a global Pause/Start button, allowing for easy manual management during printing.
Extensive Firmware & Mainboard Compatibility
Firmware: The dedicated pin works seamlessly with mainstream Firmwares like Klipper, Marlin, and RRF via their Filament Runout / Endstop interfaces.
Mainboards: Fully compatible with FLY-C5/C8, FLY-D8, Tool-Lite, and Tool-SHT36 V3 mainboards.
Printer Models: Compatible with Bambu Lab, Creality, Vzbot, Voron, and most FDM printers on the market. (Installation Tip: Please tilt the buffer upwards during installation for best performance).
Future-Ready Multi-Color Expansion (DIY AMS) This is one of the most exciting features! It supports multi-unit mounting. Via future firmware updates, users can link multiple LLL Flux units together to build a low-cost DIY AMS (Automatic Material System) for effortless multi-color printing.
🛠️ Technical Specifications
Item
Specification
Control Board
PlatformIO + Arduino STM32F072CB
Driver
TMC2225-5A * 2
Sensor
JSM603 Linear Hall Sensor (SOT-23 Package)
Motor
17HS4023-1.8° Stepper Motor
Gear Material
Brass * 2 + Hardened Steel * 4
Shell Material
PETG Printed Shell + Metal Parts
Dimensions
237.1 x 65.3 x 61.2mm (Main Body) + 131.6 x 26.3 x 20mm (Buffer Arm)
Weight
625g
Input Voltage
DC 12-24V
Conclusion
The Mellow LLL Flux Buffer is a hardcore accessory born to solve real-world pain points. It not only resolves "runout anxiety" through its dual channels and smart buffering but also demonstrates an exceptionally high level of engineering design through its mechanical cutting and extensive compatibility. For players looking to upgrade their existing printers or build a low-cost multi-color printing system, this is absolutely a choice worth watching.
