Any news on AMS loading and unloading issues?

Hello everyone and thanks for your contributions.

I am very satisfied with my X1 Carbon, very frustrated with the functioning of the AMS.

In fact, most of the time the filament loads correctly (although sometimes the error “Failed to feed the filament into the toolhead” appears).
In any case, the error “Failed to pull out the filament from the extruder” ALWAYS appears.
I have tried many filaments but the error always appears and it is enough for me to manually disconnect the bowden coupler behind the printer and ask the machine to try again because it can actually recover the filament.

Until now I tried without success:

  • I printed and tried every kind of support found online to put on the extruder so that the bowden tube follows a soft curve and enters the extruder perpendicularly to it;
  • I replaced the whole extruder unit with a new one;
  • I replaced all the PTFE tubing with new 2.5mm x 4mm tubing.

I use Bambu and eSun filaments and my only fault was having installed the AMS under the printer instead of above it due to space constraints.

I’ve read of other users having the same problem as me, is there a solution?
Thank you all

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I have the same problem and I have opened a ticket. They told me it was because there were too many restrictions. I even installed ptfe tubes with an inside diameter of 3mm but the problem persists. I cleaned and checked everything. There are no restrictions. I await their next recommendation.

You will want to make 100% sure that all of the PTFE tubes are pushed fully into their respective couplers

Back when I swapped out all of my PTFE tubes for Capricorn tubing I found a few of the factory tubes were not fully pushed forward

I swapped out my tubing almost right away so I’m not sure if or when that would or could have caused issues

Only reason I swapped out for the smaller ID Capricorn for 1.75mm filament was personal preference

100% never had a problem with the Capricorn swap and I’ve squeezed out hundreds of prints

I’m not suggesting you do the swap (I do recomend it though) but take the time and release each one then push it fully forward, you may find one or more causing just enough of a difference to cause feed issues or retraction issues especially at the buffer and the junction from the buffer to the extruder

I got the failed to pull out the filament warning tonight for slot 3 and a couple of overload messages

The AMS feed funnel on slot 3 is worn with a ridge on one side (I’ve been using slot 3 for PA/CF which is abrasive)

I loaded up a spool in slot 2 with the same filament selected AMS filament backup, cut the filament and let slot 3 run out, then slot 2 took over and its been printing for 2 hours without issue

I ordered 6 spare feed funnels immediately (they’re cheap) and will swap it out as soon as they arrive

That could very well be your issue as well

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Thank you all for the support.
The retraction error also occurs without the top glass; since Bambu Lab claims that the bowden tube must enter the extruder perpendicularly, after removing the glass I also tried to print two types of supports for the tube to make a smooth bend; I also tried a kind of small cylinder about 1.5cm high on the extruder mouth which gave vertical support to the tube but it didn’t help.

After replacing the entire ptfe line, I also tried disassembling and cleaning the filaments hub, unfortunately to no appreciable result.

I checked the feed funnels and visually they are perfect; I will have printed less than 1 kg of filament with the AMS.

I tried with PTFE tubes with an internal diameter of 1.9 and 2.5 mm (Capricorn is about 1.9) but in my case it didn’t help.

I’m convincing myself that I stretched the PTFE tube between the printer and the AMS too much; it is now about 120 cm long.
I did it because the AMS is under the printer, since I didn’t have space above it.
After trying every possible solution, today I will attempt to shorten the PTFE tube.

I’ll keep you updated, thanks again for the help.

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I had changed all my PTFE for capricorn. However, the wire caught on the edge of the capricorn when it entered in the connector junction due to the too small diameter.

I installed PTFE tubing with an ID of 3mm but that didn’t solve my problem.

Since yesterday, my AMS is no longer recognized by the printer, just flashing red in both ports. My connectors are all OK. I think the AMS circuit board is faulty. I am waiting from Support response to see if they will send me a card or an new AMS under warranty. Otherwise I think I have to buy myself a new AMS

Im sure you are already aware of the connections at the rear of the AMS that go to the board but also check the connections at the AMS feed assist that plugs into the side funnel/drive motor assy

If you already have checked those connections and wiring I’m out of simple ideas

As for the Capricorn PTFE, when I swapped mine out I did them 1 at a time as they are not all equal length in particular the ones inside the AMS itself

I really really hope that your issue is simply a pinched wire or pulled connection at the feed funnel because what you are experiencing sucks and as part of the 3d printing community I like to see people printing happily and resolving issues as I know all too well how frustrating this can get

Keep us posted and I’m hoping you get it sorted sooner than later

Some things I’ll add is are “obvious” ones, but sometimes we miss the obvious …

Make sure when you cut the tubes you:

  1. Use a sharp blade. Thinner is better.
  2. Inspect the end carefully to be sure it’s a square 90° to the tube.
  3. Ensure the hole is fully open. I use a drill bit about 2x the filament size and smooth the inner edge. Makes a nice taper for the filament to feed.

I’ll second the Capricorn tubing. I haven’t changed mine yet but 1st sign of wear and it’s gone.

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Thanks for your suggestions. I am an electrical engineer by trade. I checked all the AMS wires for continuity and they are all good. I even inspected all the welds. I also checked the voltages and they are all correct too.

I don’t understand why you can’t buy the AMS electronic card on their website. I hope they will add these parts.

For the capricorn I removed it to check if it was not because of that that I had problems. I’ve never had a problem with capricorn so far. THANKS

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I thing that I have the same problem. For me the stepper motor on the output is the problem. I thing. It get warm and stop to work. Just opens the ticket. Let’s see what will happen.

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Thank you all for your interest and advice.

I want to clarify that I’m not really a 3D printing virgin even if I’m not an expert.
Before the X1 Carbon I printed for three years with my Ender 3 which over time, like everyone else, I adapted to my needs.

I have to clarify this to explain that I have a minimum of familiarity with bowden tubes and for this reason the first solution I tried was to replace the entire line, even with the Capricorn tubes I had at home.
Since I’m no engineer and the Capricorns had no effect I replaced them with a 2.5 x 4 mm tube; the Capricorn tubes have an internal diameter of about 1.9mm while those of the Bambu of 2.5mm.
I told myself that if any engineers factory-installed 2.5mm tubing they must have had their reasons…

I also tried to smooth out any bends that felt too tight and went so far as to remove the ptfe splice at the back of the printer by installing a single piece of tubing from the hub up to the extruder.

To update you: I shortened the tube that goes from the AMS to the printer, before it was 110cm and now it’s about 85cm.
I then removed from behind the printer every object that could even touch the ptfe tube (noise filter and lateral support for the spool).
Now, with the short tube and no contact with anything else, things are much better.
I went from a certain block to a sporadic retraction block from time to time.

In my opinion, the real problem is the low torque exerted by the motor of the so-called “AMS filaments hub”.
I don’t think it’s a problem of engine strength, but rather the impossibility for the user to be able to configure the thrust force as his needs change.
I have the impression that when the AMS control logic detects a certain resistance (factory configured within a strict parameter), it blocks loading or retraction.
I think an “auto-configuration” function of the thrust and retraction torque of the motor could be useful; in this way, if over time the user varies the length of the hose or something else, he will be able to restore the right amount of force to the motor.

I hope what I wrote is understandable, it is the result of an automatic translator.

Thanks again everyone

FWIW, I have a brand new Carbon X1 with AMS. I am also experiencing the “failed to extract filament from the extruder issue”. I must manually extract the filament after every print. A YouTube video saved me much effort by suggesting that I can just disconnect the feed tube in the back, “jiggle” the filament, and then reinsert the tube into the connector. That seems to work every time - but is a major inconvenience. I’m hoping to find a reliable fix.

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It’s been 5 times that BambuLab has responded to my ticket. They told me to check the restrictions, if I had stuck filaments, the connections of my connectors, the wires etc… I just go around in circles. I’ve taken my AMS to pieces 20 times and checked everything they tell me. Last week, my AMS started flashing red twice so nothing works now. They replied to me that there was a detection of filament in both: the first-stage feeder and the AMS filament hub. How can I have two detections when I couldn’t even put a wire in it. They know it well, because I aleady told them that I had checked everything. I will once again tell them that everything is correct. I think the electronic card is the problem. I hope they will give me a real solution instead of making me do the same checks over and over again.

I feel your pain on the headaches of AMS not unloading. I have had that off and on since I got it. So far the one thing that has seemed to help has been printing and installing these.

Bambu AMS Feeder Button (w/PTFE tubing)

I just printed mine out of PLA. I think the reason these have helped is that they reduce the sharp angle between the filament and 1st stage feeder opening thereby reducing the load required to pull the filament back.

This is what I have been doing.

Agree with @PaulT that the Feeder Button will probably fix your problem.

That’s what I think was the issue on mine as well. That the filament was coming in at too hard of an angle and was digging into the funnel and catching on it. The Feeder Button along with PTEF tubing keep it going in nice and straight.

Originally I thought the whole funnels were bad and ordered 4 new ones, but several others in this thread have had success with a Feeder Button fixing the issue so I’m hoping that’s all it is.

@Jrock also had this problem and ordered new funnels, but the Feeder Button fixed the issue before his arrived. He reported that his new funnels appear to be made of different plastic, so we’re hoping this isn’t such an issue on the AMS and new funnels moving forward. I’d still recommend Feeder Buttons to anyone, even if you aren’t having the issue yet, as the funnels are a wear and tear item.

I was pondering what to print the buttons out of and that led to a quick dive into the most abrasion resistant filament. It’s a moot point if you use the PTFE tube version, but if you want the original button design you want them to last.

The winner by clear margin was IGUS filaments. For those not familiar, IGUS is the company (German?) that makes ultra low friction bearings and gears. I suspect the bearings on our printers for the X axis are from them.

They have a number of ultra low friction filaments, but the price range varies from about $60 USD for 750g reels to over $775 per reel. :astonished: :exploding_head: :face_with_spiral_eyes:

$60 for 750g is expensive but not out of range for most X1C owners.

If you’ve an interest in their offerings - 3D Printing Filament | igus®

On an unrated note - They do offer 3D printing services and also have a free access CAD Library that has Gears, Sliders, and Bearings that you can insert into your fav CAD app.

https://www.igus-cad.com/

I went with the PTFE version solely for wear

Easier and faster to replace a small piece of tube than to reprint a new piece

As for functionality of the different versions they all serve their purpose which to me is more of a guide for the filament to feed straight

The fact that PTFE tubing is slippery might aid in reducing the force needed from the assist motors but that would be the ‘moot’ part of the conversation lol

Bottom line is they work beautifully and I’ve definitely been putting them to the test

I suspect this the way I will go, mine aren’t being naughty (yet) but I favor the PTFE tube version and may go with Capricorn since I have some handy and it’s even tougher than standard.

I primarily wanted to share the IGUS info, we all love to have extra arrows in our quivers, eh?

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Many many thanks for your advice.
All the solutions I’ve tried so far initially seemed to work, the one you suggested really works.
I printed it in pla+ and inserted a piece of PTFE about 3 cm., so far no blocks!
Obviously I will come back to update you, for now thanks again to all.

Thanks for the advice.
Igus is a fantastic material even if a little expensive.
A couple of years ago a friend lent me some to make the gearbox gear for my daughter’s electric quad; the quad still runs beautifully!