I have an SV08 on Mainline Klipper with a Micro-Swiss hotend and high-flow CH2 nozzle.
My last several prints, using PETG, the print gets through 10 or more layers and then stops extruding filament. The printhead continues to move on all 3 axes, but no filament comes out.
When I pause the print, sometimes I can extrude filament using the button on the KlipperScreen, sometimes I have to unload and reload the filament. Of course, all of the prints are ruined becuase the printhead continued to register that it had printed the layers.
The heatsink fan is running at 100%.
There’s no clog that has to be cleared.
Retraction is set to 0.5mm with retraction speed set to 30 mm/s.
Lowering the print speed to 20mm/s hasn’t helped.
For temps I’m running the extruder at 245 and the bed at 75.
I’ve taken the toolhead apart and cleaned the extruder, but it’s fine.
I guess that the first thing that I would do is to check that the extruder’s stepper motor connections are firmly in the board.
The next thing that I would do is to take the section of bowden tube off and run the filament bare-nekked to the extruder. I had a cursed roll of yellow PLA that was 1.80mm in diameter and that was enough to get the extruder to skipping.
And finally, start the same print and observe if the knob on the back of the extruder motor stops spinning. That will definitely narrow things down.
I wonder if this could be a symptom of the axle backing out like was reported late last year.
Idler gear axle slips out and drops tension off the filament.
Yes, I checked the tension on the gears. I’ve noticed that was an issue once before so I keep it pretty tight.
No, the filament isn’t tangled. But I have been feeding it from the filament dryer. I had a print fail this morning feeding that way so I’ve taken the filament roll out of the dryer and it’s hanging on the side of the printer now. We’ll see how this goes.
I’m not sure, but in the case of the axle backing out, wouldn’t I have to fix it somehow to resume printing? When the printer stops extruding I can unload/reload the filament and it goes right back to printing.
Thanks for all of the suggestions! I’m going to keep trying to run this down.
I found that BTT sells a module that is not only a filament out sensor but it also monitors if filament stops moving. If the filament stops feeding, it pauses the printer as if the filament were out. That would alert me to an issue and possibly save the print. I’ve ordered one of those, I’ll let you know if it’s worth the effort.
I installed the BTT filament sensor yesterday and I LOVE it! I only connected the filament movement sensor, but that gets me all the features - filament movement, filament out, filament tangle, and extruder issues.
Last night I started a print that has failed the previous 2 nights. TWICE the BTT sensor paused the print instead of failing it. I was able to unload/load the filament and resume the print. The filament was barely in the extruder when I unloaded, I’ll have to look into that.
I just added some code to have the printer send notifications to my devices when the sensor pauses the print and when the print is complete. The printer’s running now so I’ll have to wait until later to test it.
Since you guys suggested it, I’ve checked the extruder gear pin and twice I found that it was backed out. I printed Valerie Moore’s fix and will install it after the printer stops later.
I also purchased the BTT Eddy and will install that this afternoon.
It’s heat creep. I’m having the same issue with PETG. I have lowered the nozzle temps and increased the print speeds and I’m still having the issue. It started after months of printing with no issues. I’m thinking it may either be a fan not working correctly or possibly a toolhead board issue.
Looking at the filament, it is highly grinded at the place where the extruder wheels stands. Looking at the portion of the filament that remains between the extruder and the hot end, it appears that the filament seems not enough gripped by the extruder. Could be a problem of spring not strong enough for hard or slippery filament.
I am continuing to do some experiments… but, for the moment, I have not found the solution…
I usually print ABS or ASA part at a temp fo 250-260°C.
I tried to increase temp by 10°C. it helps apparently: the problem has not disappeared but seems to come later in the print sequence. Indeed, it appears only on big prints with long and fast extrusion.
I will have a look to the hotend temp to see if it helps.
Finally, I have found the solution of all extrusion issues of the printer. I have replaced the bowden tube guide the filament up to the extruder by a high quality one (Capricorn PTFE tube).
It seems the bowden tube provided with the printer is not appropriate, which I suspect to become even stickier during the heating of the chamber.