Has anybody come across this issue: filmanet runs off spool, still in the ptfe but print is ready so printer cant retract and next time I want to print filaments crash. Why isnt there a protocol to flush the rest of the filament, or even a notification that there is still filament in there? Thanks.
One question that may help narrow this down: when this happens, has the tail end of the filament already passed through the CFS Filament Outlet Module and buffer?
If it has, then the remaining filament is downstream in the PTFE path and is no longer physically connected to the spool, so the CFS cannot retract it normally. In that situation, I would expect the printer either to purge the remaining filament automatically or at least warn the user that filament is still present in the feed path before the next print.
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exactly, but it doesnt do anything, the filament came but crashed into the previous one and ultimately found its way through the ventilation openings of the hotend cover
What that suggests to me is that the remaining filament is somehow not being detected correctly by the filament sensor in the extruder.
The only time I had something similar happen on my K2 Plus, the filament broke during retraction. It had retracted far enough that the printer apparently believed the unload had completed, but a piece of filament remained in the feed path.
That doesn’t completely explain your situation, though. If there is still a loose length of filament in the PTFE tube, the next filament loaded by the CFS should eventually push that piece forward until it reaches the extruder filament sensor. At that point the printer should detect filament, rather than simply continuing to feed as though the path were empty.
I would check the extruder first and make sure there isn’t a small piece of broken filament, debris, or a blob interfering with the filament sensor.
There is also a useful indicator on the K2 Plus that is easy to overlook. Behind the extruder cover is a blue LED for the filament sensor. When the sensor detects filament, the LED is blue; when no filament is detected, it is dark. It is much easier to see with the chamber light turned off.
Here’s an example where I am manually pulling and pushing filament through the extruder. The LED remains solid blue whenever filament is present. This is one reason I operate my K2 Plus without the hotend cover, it let’s me spot the filament sensor directly.