HomoFaciens’ direct granule FDM extruder reaches Version 7.1 after design changes aimed at making manufacturing simpler. The update removes a brass insert from Version 7.0, extends the heating element, and is now being tested for flow consistency—on a Prusa Mk
FDM printing lives and dies by one unglamorous detail: whether the extruder can deliver a steady flow. For granules as well as filament. that consistency is the make-or-break challenge—and in Version 7.1 of HomoFaciens’ direct granule FDM extruder. the project is taking a hard look at how close it can get to something you’d actually trust in production.
Version 7.1 isn’t just a quiet tweak. The update is being worked through with a series of printing tests meant to measure performance in practical conditions. An accompanying blog post also shares project files for anyone who wants to follow along.
A central change in V7.1 focuses on simplifying manufacturing. In Version 7.0, the design used a brass insert. That insert is gone in Version 7.1. replaced by a process that leans more on hands-on preparation: using a drill bit and a hand reamer to get the inside of the extruder tube just right. It’s a tradeoff—less complexity in parts, more care during assembly.
The heating section also gets a longer layout in V7.1. The expectation was that the change would translate into better results, but testing suggested the added length didn’t have as much effect as anticipated.
Even with those mixed expectations, the first round of test outcomes look encouraging. During trials, the extruder was able to keep up with bridging tests. Just as importantly, the project reports that the feared problem of air bubbles—air intruding into the tube—stayed absent.
Testing isn’t happening in a vacuum, though. On the Prusa Mk4 FDM printer, some testing features—like input shaping—can’t be evaluated cleanly. The project notes wavy patterns showing up in some rest prints. which could muddy the read on what the extruder design is truly capable of. For upcoming tests, a different FDM printer is planned, with the goal of revealing the extruder’s potential more clearly.
The project’s progress is also shared through an embedded video: https://www.youtube.com/watch?v=E4mUDcB8V3Q .
For now, Version 7.1 has landed in a place that’s less about promises and more about measured behavior—steady bridging, no air bubble issues reported, and a manufacturing simplification that shifts work from hardware to hands.
FDM 3D printing direct granule extruder HomoFaciens Version 7.1 Prusa Mk4 bridging tests heating element air bubbles input shaping manufacturing simplification open project files
So it’s basically a glue gun for 3D printers now? Cool I guess.
If they removed a brass insert, doesn’t that mean it’s gonna overheat or wear out faster? Like brass is there for a reason.
Wait they’re using granules, not filament, right? But they said Prusa Mk4 “lives and dies” on steady flow… isn’t that the whole point of input shaping too? I’m confused. Also wavy rest prints sounds like the opposite of production-ready.
I watched the video (kinda) and it sounds like they’re just doing hand reamering with a drill bit?? That seems like it depends way too much on who’s assembling it. They say no air bubbles which is great but wavy patterns?? That feels like “almost” but not quite. Also sharing project files means people are gonna copy it and mess it up lol.