Tired of your Bowden tube popping out from the top of your K2 Plus extruder without a clear solution? This custom retainer provides a simple fix. It clips onto the extruder housing and secures with a short M3 screw in the heat-set insert on the right side of the gear assembly. Install a PC4-M6 or PC4-M10 connector in the threaded hole—this will be the new mechanism to retain your Bowden tube. Then slip the notch into the slot on the left, rotate the right side down to snap over the brass insert nub, and tighten the M3 screw to lock everything in place. I recommend using a higher temp filament like PETG or some thing similar.

When using the PC4-M10 the Bowden tube should still feed through and into to the original connector and install normally once secured. If using the PC4-M6 you should remove the lid as the tube does not feed through the fitting and the Bowden tube will be quite high and intersect the lid in most cases.

Key Features

Easy Installation: No need to remove the gear assembly—just clip it on.

Retained Functionality: No need to remove the retainer if you need to clear an extruder issue, like a jam. This design retains access to all 3 screws retaining the gear cover and can be removed as normal.

Secure Connection: Uses a PC4-M6 or PC4-M10 fitting/connector for a reliable hold on the Bowden tube.

Minimal Hardware: Requires only one short M3 screw (utilizes the existing heat-set insert) and PC4-M10 or PC4-M6 pneumatic fitting.

Latest Update: Revised to use a PC4-M6 or PC4-M10 fitting to double the likelihood someone could have the parts on hand for a quick fix with minimal additional parts. The M3 screw hole on the right side has been reinforced to ensure better durability.

Caveats
The original I made was Grey PLA for about 60 print hours over 7 days without issue, but there were issues reported by others so results may vary if you go with PLA.

The PC4-M6 versions are not yet extensively tested. Because the Bowden tube does not pass through the filament may not reliably pass into the extruder 100% of the time. That said I have not yet had any failures to feed or retract during a change. I will continue to test and update if there are any issues. Please use PC4-M6 with caution and, as always, at your own risk. If you do run into a problem please comment and I will try to improve the design or pull it down if it is not viable.

Thanks to Cupcake155 for the feedback, and testing as well as creating a remix.

Cupcake155

If you have any questions, suggestions, or improvements, feel free to comment. Happy printing!

Bowden Tube Retainer for K2 Plus Extruder

0.2mm layer, 3 walls, 20% infill

0.2mm layer, 3 walls, 15% infill

Remix Models