Prusa XL Filament Feed Block

Intended Design/Use

In my opinion, the experience of loading filament into the Prusa XL feels less polished than my MK4s. I don't like the way the short bits of PTFE tubing jut out of the sides at different angles making filament loading cumbersome. It feels a bit clumsy and looks unfinished. I set out to see if I could improve that experience.

My designs and implementation also have flaws and limitations. However, I notice a significant improvement when using these parts on my XL and I wanted to share that with anyone else who might appreciate the effort.

I created a housing block that slides over the PTFE tubes and butts up to the face of the OEM filament entry part. This holds everything together through a friction fit (fairly tight tolerances were chosen), hides the bare tubing, and visually extends the lines/shapes of the printer.

Each individual PTFE tube is then capped with and small inlet fitting. These were designed to increase the target area for inserting filament, feature a chamfer to help funnel the filament to the opening, and also act as a fitting to keep the block from backing away from the mating surface.

When everything is properly installed, it feels pretty solid despite not having any fasteners. Granted you will feel some “give” as you push on it, but it shouldn't feel too loose or flimsy. It can also be removed by carefully pulling the block away from the OEM part.

Printable Parts

XL_filament_feed_block.stl
XL_filament_feed_inlet.stl

Print Settings

0.2mm Layer Height
2 Perimeters
15% Infill
No supports required

Assembly Instructions

First, check the length of the PTFE tubes coming out of your XL. Mine all stick out about 23mm when measured from the face of the OEM printed part (with 1, 2, 3 printed on it) to the end of the tube. I made the assumption that this is consistent across XLs shipped from Prusa. See the following images for reference.

If your PTFE tubes are longer and stick out more than that, you may not get a snug fit and may have issues assembling the parts properly. There will also be fitment issues if they are too short.

Guide the XL_filament_feed_block part over the PTFE tubes. The fit inside each hole is tight. So, go slow and only use reasonable force.

Press it all the way on ensuring it clears the collets and butts up flush.

From the front, you should see each PTFE tube more or less centered in the inlet holes like the image below.

Take each of the XL_fillament_feed_inlet parts and carefully insert them into the front holes taking care to make sure they fit over the PTFE tube ends without damaging them. The image below shows the start of pressing an inlet part into the top hole. The final position of the inlets when fully seated will stick out 1mm from the front face of the block.

Here’s what the fully installed assembly should look like:

Notes

* For personal use only
* Not for sale