RX TOOLHEAD V5.5 using Bambu H2S/A1 gear & H2D Hotend

 If you need quick help or just hanging with us, talking about this toolhead

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Full step-by-step NEW Assembly Video 

⚠If you are using the H2S extruder, don't skip this part! bellow

You’re chasing top-tier print quality without breaking the bank, this DIY Bambulab H2D/P2S style of toolhead is a game-changer. — It’s modular, efficient, and full of smart upgrades.

✅ Why Build One?

• Compatible with Bambu Lab H2D, P2S, A1, P1S, and X1C hotends.

• Compatible with H2S and A1 extruder gears.

• Delivers exceptional print quality while remaining compatible with Bambu Studio print profiles.

• Designed with continuous improvement in mind—the designer actively maintains and updates it based on real-world testing and community feedback.

   

• Supports 6 and 9 mm belts, for default VORON SV08 and Monolith gantries

• Carriage for MGN12H and  MGN9MM rails mount
  Modular and fun: Since the front cover is detachable, you can quickly swap it for the Pen Plotter module and turn your printer into a drawing machine. (example here )

• Quick-swap nozzles — Get back to printing in seconds. Thanks to the Bambu Lab hotend heating assembly, nozzle changes require no contact with the thermistor or heater wiring, eliminating the common risk of damaging thermistor cables during swaps.

• Modular design — Easily upgrade, replace, or service individual components.

• Integrated filament sensor — Built-in for a clean installation and reliable filament detection.

• Automatic filament loading — Smooth, convenient, and user-friendly.

• Lightweight toolhead — Optimized for input shaping, high-speed printing, and precise motion.

• Affordable components — Compatible clone parts are widely available, making maintenance and upgrades cost-effective.

• Engineered for reliability — A robust mechanical design built for long-term performance.

• Clean, professional design — Looks and performs like a refined production toolhead, not a typical DIY project.

Supports Different Probe types

Very easy to assemble and maintain

Visual Guide

📦 Materials (BOM) – Organized by Category

All items include direct purchase hyperlinks

⚠ Note About Links & Purchasing

Some of the Amazon links are affiliate links, provided only as a reference for part specifications and compatibility.
You are not required to buy from Amazon, and I don’t mind where you purchase the parts from.

My main goal with this project is to keep it as budget-friendly as possible so more people can build, experiment, and enjoy this toolhead.
Feel free to source parts locally, from eBay, Taobao, Bambu Lab, or any trusted supplier, as long as the specifications match.

⚠Also, pay attention and don't just buy everything on the list, some are duplicated. Just choose what you need ‼

RX VORON V5– 5015 Toolhead BOM

🔩 Fasteners & Hardware

• M3 Screw Assortment Pack – M3×6/10/12/14/16/25/30 + M3 Nuts → Amazon

• M2×10 Self-Tapping Screws ( for standard limit switches) → Amazon

• M3 Brass Heat-Set Inserts (30× short M3×5×5) → Amazon

• D6x3 Round Magnet (buy 8 or more) Amazon

🔌 Tubing & Connectors ( Pogo Pins are optional and you can also run the cables directly if you want)

• PTFE Tube + ECAS04 Connector → Amazon

• PG7 Cable Connector (only if using EBB36 v1.2) → Amazon

• 2-Pin Pogo Pins→  Amazon 

• 2-Pin Pogo Pins ( optional; you can connect LED or RGB using rounded pogo 2 pin → Aliexpress

🌀 Cooling Fans 

         (⚠Pay attention to the voltage according to your toled headboard voltage requirement)

• 2510 Fan (hotend  fan) → Amazon

• 5015 blower fan  →  Amazon

🎛 Electronics & Boards

• EBB36 1.2 Toolhead Board → Amazon

• EBB36 GEN2 Toolhead Board → Amazon

• Neopixel RGB LED Strip (optional) → Amazon

   

🔥 Heating Assemblies ⚠

Original Bambu Lab assemblies strongly recommended. DO NOT buy H2D Left – Right is easier to work with.

• Bambu Lab A1 Heating Assembly → Amazon | Bambu Lab Store

• Bambu Lab H2D Right Heating Assembly → Amazon | Bambu Lab Store

• Bambu Lab P2S Heating Assembly → Bambu Lab Store

🔍 Probes (⚠choose one)

• BTT Eddy Probe → Amazon

• MicroProbe → Amazon

• Cartographer Probe → Official Website

• Beacon Probe → Official Website

⚙ Extruder Gears (⚠choose one)

    New recommendation to buy the

• H2S extruder gear, it is a bit better than the A1 gear, especially if you plan to print TPU.

  Also, it comes already with a compression tensioner spring, but it has no bearings in the package, so you will need to buy bearings separately, link below, Bambu Lab Store

   

• if you buy another 3rd-party extruder gear or if you buy the H2S extruder gear, they don't include bearings in the package, so you need to buy the bearing separately thats. MR104 ZZ Amazon

   

   

• Original Bambu Lab A1 Extruder Gear ( includes bearing but has no spring) – Amazon | Bambu Lab Store

• BIQU Alternative Extruder Gear (good for abrasive filaments, also includes bearing but has no spring) – Amazon

   

🌀 Springs

• Torsion Spring 1×5×3 – 120° (for filament cutter) → Amazon | Bambu Lab Store

• Compression Spring (0.8mm Wire Dia, 5mm OD, 10mm – for extruder tensioner) → Amazon

🧷 Pins, Blades & Switches

• 3×20 mm Dowel Pin (for filament tensioner; alternative: M3×20 screw) → Amazon

• A1 Filament Cut Blade → Amazon | Bambu Lab Store

• 13mm × 5.5mm Limit Switch → Amazon

• Small Switch KFC-V-105S-2-T ( alternative used for double filament sensors only) → Ebay | Alibaba

🔥 Hotends (⚠choose the one you need). 

Match your hotend to your heating assembly. Mixing A1 heating assembly with H2D hotend gives almost no flow improvement.

• H2D Normal Hotend (~42 mm³/s PLA) → Amazon | Bambu Lab Store

• H2D High-Flow Hotend (~58 mm³/s PLA) → Amazon | Bambu Lab Store

• A1 Hotend (~25 mm³/s PLA) → Amazon | Bambu Lab Store

🔧 Motors & Wiring

• P1S / X1C Extruder Motor (gear is Helical) → Amazon | Bambu Lab Store

• 26 AWG Wire (for proximity switches) → Amazon

• Servo Motor (optional – for filament cutter) → Amazon

🟢 One-Stop: All-Original Bambu Lab Parts 

Purchase directly from Bambu Lab for guaranteed compatibility:

• A1 Filament Cutter Blade → Bambu Lab Store

• H2S Extruder Gear Assembly (Recommended)→ Bambu Lab Store

• A1 Extruder Gear Assembly (alternative)→ Bambu Lab Store

• A1 Heating Assembly → Bambu Lab Store

• H2D Right Heating Assembly (recommended higher flow rate)→ Bambu Lab Store

• P2S Heating Assembly (almost the same as H2D) → Bambu Lab Store

• H2D Normal/High-Flow Hotends → Bambu Lab Store

• A1 Hotend → Bambu Lab Store

• Torsion Spring 1×5×3 (120°) → Bambu Lab Store

💡 Pro Tip: Bookmark this list! Double-check compatibility before ordering, especially for heating assemblies and hotends. When in doubt, buy original Bambu Lab parts for best results. 🛠✨

If using a static filament cut depressor,  to prevent the toolhead from crashing, configure an excluded zone in your slicer according to the depressor’s XY position. 

⚠ After installing this toolhead, remember to update your slicer settings for retraction and deretraction speeds.

Also, don’t forget to update the extruder rotation distance and heating assembly sensor type in Klipper to the value below:

rotation_distance:  4.7979
sensor_type: Generic 3950    #Must use this for Bambulab sensor type 
pullup_resistor: 4700             #for ebb36 gen2  default use 2200
min_extrude_temp: 0                   #important if you will use my load unload filament macro, keep it 0
max_extrude_only_distance: 300.0       # #important if you will use my load unload macro
max_extrude_cross_section: 10.0

I have attached a .txt file below with all important Klipper settings and macros for  proper use of this toolhead 

 💡I’ve noticed that most people tend to comment or share photos only when they run into issues. But this toolhead represents over a year of work, iteration, and improvement to become what it is today.

So I truly appreciate everyone who takes the time to share photos of their builds — not just problems, but successes too. It really means a lot and helps show what this project can achieve in the real world.

Thank you for being part of it 🙌

Enjoy the future of DIY printing!

Happy printing!

____________#######____________

🔧 Common Issues & Fixes

1. Extrusion Inconsistency

Possible causes & checks:

• Rotation Distance

• Make sure your rotation_distance is set correctly as specified in the provided .txt file.

• Sensor Type

• Verify that the correct sensor type is set correctly as specified in the provided .txt file.

• Filament Tensioner Adjustment

• Proper tension is critical.

• Tighten the screw without filament inserted until you see slight movement, then stop.

• Too tight → filament deformation

• Too loose → slipping / under-extrusion

• Spring Selection

• You can use different springs, but:

• If the spring is too soft, it will cause inconsistency at high flow rates.

• Recommended: ≤ 0.8 mm wire thickness

• Weak springs = unstable extrusion under speed

• Filament Sensor (Switch Type)

• If installed:

• Enable pull-up resistor in Klipper (^ symbol)

Example : switch_pin: ^EBB:PD0

• Without it:

• You may get false triggers

• This can unintentionally activate load/unload macros → causing inconsistent extrusion

2. Heating Assembly Melting mainbody mount

• If your chamber temperature exceeds 55°C and you are printing at a nozzle temp over 260c.

• Use high-temperature materials to print mainbody, such as:

• • PAHT-CF

• • PPS

• • PA12-CF

• • Alternative:

• Use the hybrid design provided on step&stl:

• • Printed body + CNC/machined high-temp components

3. Filament Cutter Getting Stuck

• Do not fully tighten the screw holding the cutter.

• Leave slight clearance:

• The spring will handle the pressure.

• Over-tightening = binding/jamming

4. Filament Not Fully Clearing After Cut

• A small piece may remain inside, making hotend swaps difficult.

Solution:

• Use the provided cutting macro

• Make sure to:

•Properly tune the XY position Align it with your cutter depressor location

5. Back Cover Hitting the Carriage

• Some printer carriages are taller than standard.

Fix:

• Use the default shorter back cover version

6. Heat Affecting Probe (Eddy / Microprobe)

• Excess heat from the hotend can damage or deform your probe.

Solution:

• Print and install the probe heat shield included in the model

7. The thermistor is reading the wrong temperature

Thermistor Pull-Up Resistor Guidance🌡

Different toolhead boards may require different pull-up resistor values for accurate temperature readings. This affects how the thermistor signal is interpreted by Klipper or other firmware.
   •    Ebb36 1.2: Works correctly with a 4700 Ω pull-up resistor.
[pullup_resistor: 4700]

   •    Ebb36 Gen2 : Requires a 2200 Ω pull-up resistor for correct readings.

Tip: If the temperature readings seem offset (too high or too low), check the pull-up resistor value first before adjusting any other settings. Using the wrong pull-up resistor can cause misreading by ~30 °C or more, affecting print quality and material behavior.
  pullup_resistor: 2200             

💡 Final Tip

Most issues here come down to setup precision, not hardware defects.

Take your time during installation:

• Follow the documentation carefully

• Double-check mechanical adjustments

• Validate your Klipper config before printing

RX Toolhead V5.5.2 Changelog

This is a major update. I recommend reprinting all parts except the carriage.
If you are using the H2S Main Body, you do not need to reprint it. However, the A1 Main Body must be reprinted.

 New Features

• Added OZNLAB Sensor support

  • Real-time Pressure Advance reading and automatic PA insertion into the start print

  • Z-offset calibration with tap

  • Bed mesh with tap

  • Nozzle clog detection

  • And more

• Added SV08 Carriage

• Added dual filament sensor support for the A1 extruder gear setup

• Added Pen Plotter Module 🖊

  • A fun mod that allows you to quickly replace the front cover with a pen plotter module

  • Draw on paper using your printer

  • OrcaSlicer profile included

🔧 Design Improvements

     > Renamed the CAD files and organized them by group, making the assembly easy to understand

• Redesigned front cover

  • RX logo moved to the top

  • Added a slot for an RGB NeoPixel

  • Fan position lowered for improved cooling

• Reduced the rear electronics section by 8 mm

• Improved extruder gearbox design

• Improved Cartographer / Beacon / Mellow Fly sensor mounts

• Improved umbilical cable holder

📦 Reprint Recommendation

Because this is a major redesign, I strongly recommend reprinting all parts except the carriage.

• H2S setup: Main Body can be reused

• A1 setup: Main Body needs to be reprinted

• Other updated parts should be reprinted to take advantage of the latest improvements.