QU-BD One/TwoUp Extruder V11 with video

Author: laird, published on 2014-01-08

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This is a replacement extruder for the QU-BD One/TwoUp printer. It replaces the wooden parts, and holds the hot end.
It replaces the wooden extruder and screws to the kit’s gantry mounting parts. Or even better, it works perfectly with http://www.thingiverse.com/thing:223327 which is a one-piece printed mount plate that clips onto the linear bearings!
It can be used two ways.

If you have a large format printer, you can print UpGrade.stl, which contains all of the parts of the extruder and also the mount, completely replacing the entire MDF assembly, making it much sturdier and easier to use.

1) Use just the body and lever, with the original screws, spring and bearing, to replace the MDF extruder. This works well, and eliminates the fiddly wooden pieces that break.
2) Add the fan venting, to attach the cooling fan to the extruder, and then blow the air down onto the print. This cools the motor and the print, but it requires updating the firmware on the controller board (as documented by QU-BD). Very optional.

  • The advantages are intended to be:

  • Easier filament release and engagement (press a button vs. screwing an M3 socket head screw).
  • Holds the hot end more firmly (mine is wobbly).
  • More durable than wooden parts (two of which have already cracked for me).
  • Integrates fan into extruder, to cool motor and filament above the hot end as well as the print.
  • Able to add a fourth screw into the motor (the QU-BD design uses three).
  • Able to print replacements
  • Parametric design so it’s easy to tweak and extend. If you like OpenSCAD anyway, which I do.
    V3 update:
  • Angled the vents from the extruder to the print to be further from the hot end. Don’t want them to melt.
  • Added guides to lock halves of parts together when assembled.
    V3b update:
  • Got the ‘plated’ items properly leveled. Oops. Prints fine now, all parts are “tight”, at least on my printer. I look forward to additional feedback.
    V4 Update:
  • Added ridges between the two halves so they align when assembled. Better than the v2 guides.
  • Made hot end even tighter.
  • Made lever longer, so it should be easier to load/unload filament.
  • Made a bit thicker, so it works with the QU-BD provided screws and MSD mounting plate.
  • Corrected some minor bugs.
  • Made a few walls thicker to improve prints.
    V5 Update:
  • Made lever much stronger. If you’re using v4, print the v5 lever and swap it in. The other parts are unchanged.
  • Generated all of the individual parts, and plates of pairs, in addition to the plate of all parts, so you can pick which you want to print.
    V6 Update:
  • Merged the FanVent and Vent parts (into FanVentPlated5.stl). Making them a single part makes it stronger. Also, angled the vent to clear an obstruction when the extruder is at the left edge of the build plate. Eliminated the wall facing the extruder body, giving more airflow and improving printability. This does require gluing the vent to the side of the extruder body to seal airflow, though.
  • Added a ‘guide’ to the lever (LeverPlated6.stl), helping keep the filament on path to the bearing and the hot end.
    V8 Update:
  • Merged the fan vent and the associated vent into one piece, so it’s stronger, and has improved air flow. Also, angled it so that it avoids an obstruction when the extruder is at the left edge of the print bed.
  • Deleted all of the old files, as it was getting confusing. These days, if you want to plate them you can do that yourself.
    V9 Update:
  • Modified vents so that it fits if the lever is routed to the left or to the right, and allows full travel on X axis.
    V10 Update:
  • Increased clearance between lever and the extruder gear.
    I’m pretty happy with this so far. You can use the extruder body and lever to replace the MDF extruder, which is quite fragile and hard to load, which was my primary goal. And you can add on a fan and venting, which will keep the motor cool and improve print quality, if you like.
    V11 Update (thanks to tommythorn for the request)
  • Spring is 2mm shorter, which should work for more people’s springs without needing to insert the spacers.
  • Spring support is much stronger.
    The pictures on this Thing show the assembly, and there are written assembly steps in the instructions tab.

Jim Younkin produced a nice video (in 3 parts) of the assembly process:

Nice job, Jim!


License: Creative Commons – Attribution – Non-Commercial

Tags: 1UP, 2UP, customizer, oneup, qu-bd, twoup