Good day,
I little while ago I started printing the Macaw project from Makerworld via the slicer on PC, nothing out of the ordinary. But at some point I noticed this grinding sound coming from my AMS (2 Pro). On closer inspection I noticed my filament buffer was somehow not triggering the AMS to feed correctly to the toolhead.
Normally the filamentbuffer”slide” slides to the left position when the printer is extruding filament. In normal operation the buffer will slide to the left, triggering a magnetic switch telling the AMS to feed, expending the filament path by feeding the filament, and triggering the right magnetic switch in the filament buffer telling the AMS to stop feeding.
From some reason, and since I started that project (not implying it’s related), the filament buffer “slide” stays in the left position when printing starts, never triggering the magnetic switch. The AMS won’t feed the filament, but the extruder will still pull filament through the system, causing the filament to grind in the AMS feeding gear (the second gear in the back of the AMS).
When I use my finger to push the filamentbuffer “slide” a little bit more to the left and keep it there for a few seconds, the toolhead will slowly move to the pause position, retract the filament, feed it back in, purge a little bit, and resume printer. After this the issue is gone. The filament buffer will function as normal and the AMS feeds the filament as intended.
Shortly pushing the filament buffer “slide” to the left and releasing it before filament pullback does not trigger filament feeding from the AMS. Since the issue is resolved after the the filament pullback and feeding, it doesn’t look like the filament buffer has a broken sensor.
This only happens with the filament that is used at the start of a print. Sub sequential filament in the same print won’t cause this issue.
I haven’t tried and test this with my left nozzle, since my AMS’ are only connected to the right nozzle.
AMS firmware is version 4.00.21.87. This is the newer firmware provided from my H2D. The firmware the H2C wants my AMS to upgrade to is the older version 3.00.21.29. Never had issues with the newer firmware before, it worked fine without issue.
Bambu Studio is the latest beta version.