Extrusion or flow dynamics issue with only 1 AMS slot?

Bambu Lab X1 Series Troubleshooting
1

I have a bit of a head scratcher. Maybe one of you smart guys can help figure it out. I am getting an under extrusion type issue that looks a lot like a flow dynamics calibration problem. See attached pictures. At first, I thought it was the new filament I was using for the first time. However, when I unloaded it and put it onto a different AMS slot and reselected a generic profile it flowed like butter. Cool, problem solved, I thought! A day later, I put a different roll of filament onto my only empty AMS slot (#4), and again I have the same ‘under extrusion like’ issue. I am using non bambu lab filament with the generic PLA settings, which work great on every slot except 4 right now. Everything worked good out of the box. The issue seems to have started when I tried to load a filament onto slot 4 during a print, which apparently AMS lite can’t handle. But all settings look good and I see nothing that would be causing this.

Also, every time it has happened I get an discontinuous (dotted or dashed) test line prior to the print. Second to last picture.

Thanks in advance for any suggestions!

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2

On the original AMS the internal gears would slip on the steel shaft spines. I had to fix one of mine with some ca glue. It looks like the AMS lit has the same gear setup, something you can check out to see if it’s slipping and not feeding filament to the tool head extruder.

Watch it when it works I was able to see it slipping on mine.

Disassemble the AMS Feeder Unit

Gears

3

problem solved? thinking i got the same issue

4

Actually, I think so. My PTFE tubes kind of twisted around one another slightly. I could not notice any resistance difference between tubes when inserting and removing filament by hand. None the less, I disconnected all 4 PTFE tubes on both ends basically made sure each one was routed directly and not crossing under one of the other tubes. That seems to have done the trick! My last 3 or 4 prints have been successful. Best of luck with yours! Let me know how it turns out.