Titanic Extruder

Introduction - What the heck is this?

I was recently given three clone Titan extruders with worn out filament guides; also, while J-Head mounting patterns are old school in 2026 I did not want to see the hardware go to waste either.

Tried printing a replacement housing and lever someone had modelled per the original but there were multiple issues with the models.

I also found out about the Titania extruder (which uses a round NEMA 14) but didn't want to spend on more steppers.

This led me to this exercise in extruder design.

Notes

• Uses the Orbiter 2 mount pattern.

• The size of your stepper will significantly impact compatibility on different printers. I ran print tests on my Voron V0.2 where it only fit because I had a thin "pancake" NEMA 17 on hand.

• I haven't designed any tool head PCB mounts; it should not be too difficult to adapt existing mounts to screw to the back of the stepper. The V0.2 PCB mount also screws into the X carriage, used that plus zip ties, a screw in the top stepper hole and a bit of filament as a shim for my tests.

• I printed in ABS or ASA with snug supports.

• Avoid icebergs.

• Do not submerge in seawater.

• CAD screenshots for the build instructions were taken with an earlier revision.

Bill of Materials

• Clone Titan extruder gear set and bearings

  • 12 mm stepper drive gear

  • 34 mm outer diameter, 66 tooth, 8 mm inner diameter, 21 mm shaft length filament gear

  • 1x Filament guide idler bearing

  • 1x MR85 bearing

  • 2x MR105 bearings

  • Tensioning screw, nut, spring

• NEMA 17 stepper motor with a 5 mm shaft

• PTFE tubing, 4 mm OD, 2 mm ID, length 14 mm + distance to hotend.

• Ball end hex 2 or 2.5 mm drivers depending on screw type used

• Screws, you can use BHCS or SHCS interchangeably except where specified

  • 1x M3x4 (x6 also fits but harder to install) to secure the front and back together on the lower right corner

  • 1x M3x4 (or M3x6 if stepper is large enough) to secure the back to the stepper underneath the filament gear

  • 1x M3x8 BHCS to secure the filament idler in the lever

  • 1x M3x10 (or M3x12 if stepper is large enough)

  • 1x M3x20

  • 1x M3x25

  • 2x M3x?? to mount to your tool head

• 2x M3 x 4.0 mm deep x 5.0 mm diameter threaded brass inserts (a.k.a. "Voron spec")

• ECAS04 fitting

• Optional - Thread locker

Instructions

1. Install a threaded insert into the lower right hole:

   

2. Install a threaded insert into the lever pivot screw:

   

3. Insert an MR105 bearing into the back part.

4. Secure the "back" part to the stepper with an M3x4 SHCS in the bottom stepper screw hole, leave it loose for now so you can adjust backlash.

5. Install an M3x10 in the left side stepper hole, leave it loose for now.

6. Temporarily install an M3x"long enough" screw in the right stepper hole to serve as a pivot for backlash adjustment

7. Temporarily install the filament gear

8. Install the brass drive gear, place the grub screws above the filament gear and make sure the entire filament gear overlaps with the drive gear. Consider adding a tiny drop of thread locker on the grub screws.

   

9. Check for backlash with the drive gear, adjust the "back" part's position as needed then tighten the left side screw to set it.

10. Remove the filament gear.

11. Tighten the now accessible bottom screw.

12. Remove the right side screw.

13. Lever preparation: install the idler and secure it with an M3x8 BHCS.

    

14. Drop the tension screw into the slot - there should be a light snap

15. Thread the tension nut onto the tension screw.

16. Tighten the screw, make sure the nut is aligned correctly, bring it to the end of its travel.

17. Slide on the tension spring.

18. Put the lever roughly in position, it cannot slide in after the front part is installed.

19. Press in the ECAS04 pneumatic fitting on the top of the "front" part.

20. Install the second MR105 and MR85 bearings into the "front" part.

    

21. Mate the front and back parts together

    

22. Install an M3x25 in the right side stepper hole.

23. Align the lever and install the M3x20 lever pivot screw, do not over-tighten, confirm lever can still move.

24. Cut a length of PTFE tubing, toolhead side + 14.0 mm.

25. Insert PTFE tubing into the filament path from the bottom.

26. Install the extruder onto your tool head, secure with two screws.

27. Secure your tool head PCB if applicable. Manage wiring.

28. Update your printer configuration if necessary, in Klipper:
    
    rotation_distance: 23.45

    gear_ratio: 3:1
    
    should be good starting points.