Project Dashboard Accessories and Upgrades LulzBot TAZ Dual Extruder Tool Head v1 Installation LulzBot TAZ 4 Workflow

1 Before Beginning

Recommended Tools
Dual Extruder Vitamins
Dual Extruder

2 Remove Current Toolhead

  • Power down the TAZ 3D printer and unplug from any USB connection.
  • Disconnect the two wiring connectors for the Budaschnozzle and the stepper motor and the wiring harness.
  • Disconnect the fan connector.
  • Using the 2.5mm driver remove the M3 screw and washer.
  • Save the M3 screw and washer.
  • Lift off the current toolhead.
Disconnect Toolhead
Remove Screw

3 Mount the Dual Extruder Toolhead

  • Slide the tapered bottom of the dual extruder into the extruder mount.
  • Secure with the M3 screw. DO NOT over tighten.
Slide Toolhead Into Groove
Secure Toolhead

4 Install Addtiional Wiring Harness

  • Insert the new additional wiring harness into the electronics enclosure by screwing it into the existing second extruder port, found on top of the electronics case.
Remove Second Extruder Cap
Cap Removed
Install Second Extruder Harness
Harness Installed

5 Secure Hot End Wring

  • Zip-tie the wire harness together if desired.

  • Use zip-ties to secure the wiring harnesses to the TAZ frame.

  • Connect the two extruders to the wiring harness:

    • Connect the rear extruder motor (extruder 0) 4 color wire connector to the 4 color wire connector within the black wiring harness

    • Connect the rear hot end (extruder 0) 2 color wire connector to the 2 color wire connector within the black wiring harness

    • Connect the front extruder motor (extruder 1) 4 color wire connector to the 4 color wire connector within the blue wiring harness

    • Connect the front hot end (extruder 1) 2 color wire connector to the 2 color wire connector within the blue wiring harness

Harnesses Secured

6 Install Second Spool Arm (optional)

  • Loosen the M5 bolt holding the first spool arm.

  • Lower the existing spool arm by ~3 inches.

  • Attach 2nd spool arm using drop in fastener. Slide the provided M5 T-nut into the aluminum extrusion approximately 6” above the original spool arm position. Make sure that spools can spin freely on both arms without interfering with each other.

  • Attach 2nd feed tube on original feed tube holder.

Insert T-nut
Secure spool arm

7 Prepare To Load The Dual Extruder Firmware

  • Use the firmware found here:

  • Locate your original steps per unit.

    • This can be found in your TAZ printer paperwork on the sheet titled Test Acceptance Record and labelled E0.
    • On your Graphical LCD controller, use the controller knob to navigate to:
      • Configuration > Motion > Esteps/mm and record the 3 digit value.
  • Update your local Arduino installation with the required libraries using this guide

8 Update Firmware

Extract the files to a memorable location.We recommend a new folder on your Desktop, or a new folder in your Home folder.

  • Extract the Firmware archive. Once extracted, you should have the following folder at least:

    • Marlin_dual_extruder_TAZ4
  • Open the Arduino IDE.

  • Select File > Open .

  • Navigate to the folder containing the Marlin_dual_extruder_TAZ4 folder you previously extracted.

  • Open the file titled Marlin.ino

  • Once opened, you should see multiple tabs across the top of the Arduino IDE window.

  • In the Configuration.h tab, update the information found in:


  • You will need to update the last 800 number with the Estep value found earlier.

On the next line:

define DEFAULT_E1_STEPS_PER_UNIT 800 // default steps per unit for second extruder

  • change the 800 value to 840.

  • Once changed save the modifications by pressing CTRL & S or by selecting in the menu File > Save.

9 Flash Firmware

  • Connect the TAZ to your computer with the supplied USB cable.

  • Once connected, in the Arduino IDE menu, select:

    • Tools > Board and select Arduino Mega 2560 or Mega ADK.
    • Tools > Serial Port and select your local active serial port.
  • Upload the firmware to the TAZ 3D printer by selecting File > Upload Sketch or by pressing Ctrl & U.

  • The firmware will now compile, then will upload to the board. Once finished, the Arduino IDE will display a completion message.

  • If you encounter any errors, contact support by sending an email to

  • Disconnect the TAZ from your computer and turn it off and back on.

10 Calibrate your Dual Extruders

Done! Take me home