I can understand your frustration if some of this isn’t your jam. I’ve helped lots of people with what the heck this thing is, and what it solves. It’s true Bambu could have done a little better job explaining things like “It still doesn’t let you put TPU in an AMS.” People like me are the ones answering those questions. I’m not going to talk to you like you’re stupid, I’m just going to explain it for anyone who wants to know.
This thing solves 3 problems. Drag, sync with the printer, and unloading retraction.
Drag is from every tube, every connection, every bend, the spool, and just about everything else that makes up the infeed. Things like filament dryers and spool holders will all add to the drag as well. This thing pulls the filament and the spool most of the way without letting the weight etc affect the filament between the module and the extruder. Without it, it’s really easy for that drag and weight to stretch the softer filaments and screw up the flow rate. An AMS is a nightmare for TPU and drag because “pushing a rope” through a tube is possible, but it’s going to be hard as heck. An AMS pushing might actually just add drag.
Normally we also use the AMS to sync our filament with the printer, but the AMS relies on the filament to push a switch in the buffer to tell it when to “push” and “pull”. TPU just sucks at doing that reliably. The infeed assist module is designed to reliably handle this job with softer materials. Sadly it isn’t for use with harder materials as well aside from poking it with PLA or PETG to calibrate it.
Lastly there’s unloading retraction. You probably already know that the bypass doesn’t handle unloading at all and that we do this manually. The TPU infeed module should handle this as well, though I’ve not seen it explicitly stated. I guess if it doesn’t then you have another legitimate reason to complain about it lol.
The top loading vs tube loading is basically just a bonus in my books, but you should still count being able to tube load TPU reliably as a win overall. It’s certainly not a loss anyway.
IN THEORY: this thing combined with a splitter with proper filament detection could let us switch between AMS hard materials and bypass tube soft materials. We’d need a splitter that talks to the machine, or at least follows g-code instructions.
I’m not saying I’m making one with another guy at this point, but it has been discussed with another guy and it could happen if Bambu doesn’t deliver the proper solution for this.
I’ve got one skill set that covers one part of the work, and he’s got another that includes the bit I wouldn’t want to tackle.
At this point there’s no reason that these upgrades shouldn’t lead to better multi-material printing.
I’ll also point out that a similar module + splitter setup for hard materials would also let us do 5-color with 1 AMS and would be even easier (mechanically speaking). That would require more firmware integrations though, and Bambu probably wouldn’t like that since it would cut into AMS sales. Still, someone will eventually do it if they don’t lol. That’s just the industry we are in.
There ya go. An explanation, some clarification, and a little bonus speculation. I’m mainly just here to clarify the things we’ve been clarifying in the forums for a while now, your post mainly just happened to be on the right topic but I hope you enjoyed it anyway. This needed to be clarified in this forum either way.
