Underextrusion and transport problems of the filament
I have severe problems with printing a simple rectangular frame with a size of 190 x 190 x 50 mm. I tried the following steps, following the advices of the support https://help.prusa3d.com/article/under-extrusion-nextruder-printers_821253 :
1. Nozzle: replaced the nozzle and recalibrated the unit
2. Slicer settings: modified the slicer setting with regard to temperature (modifications in the range of 210 °C ... 230°C) and printing speed options
3. Gearbox: recalibrated the gearbox
4. Filament: Used new and different filaments Prusament Galaxy (black) and Gravitiy (grey)
Observations:
- Printing the first layer is good. The material sticks good to the plate
- After a while the filament extrusions is reduced or even the transport of the filament stops
- Noise can be heard from the extruder similar to a chattering, vibration.
Question:
Should I replace the idler leveler (A, B) or the extruder main plate. Is there any stepwise approach to find out the real root cause of the failure?
RE: Underextrusion and transport problems of the filament
What kind of filament are you using? Is it PLA? Seems maybe your filament is clogging the nozzle.
Without a picture of the issue we can't do much more than guess - but the first thing I would check from your description is the extruder idler pressure.
To clear any possible partial clog I would first do a cold-pull.
To reduce the effect of infill back pressure change to either cubic or gyroid infill and re-slice.
Print - it might now be fixed (unlikely) but if not tweak the extruder idler pressure, it could be out either way so keep careful count of the turns; I would begin with half a turn at a time, test printing in between. If that doesn't help undo all the turns, print again and show us a picture of the problem
Cheerio,
RE: Underextrusion and transport problems of the filament
I tested the setup with two different PLA Filaments The first one was Prusament Galaxy (black) and the second Gravitiy (grey). I had similar problems with PETG and a hotend temeparture of 245°. Clogging shouldn't be the problem. As written before I changed the nozzle and in addition the first layer priniting and some following layers is ok. In my opinion after appr. 30 - 60 min the underextrusion starts.
RE: Underextrusion and transport problems of the filament
Without a picture of the issue we can't do much more than guess - but the first thing I would check from your description is the extruder idler pressure.
To clear any possible partial clog I would first do a cold-pull.
To reduce the effect of infill back pressure change to either cubic or gyroid infill and re-slice.
Print - it might now be fixed (unlikely) but if not tweak the extruder idler pressure, it could be out either way so keep careful count of the turns; I would begin with half a turn at a time, test printing in between. If that doesn't help undo all the turns, print again and show us a picture of the problem
Cheerio,
Thank you for your advice. I will start the printing again and will take some pictures and publish them here in the forum.
Regarding your first proposal: I will clean the transport unit "idler leveler (A, B) or the extruder main plate" and adjacent parts of the extruder with pressurized air. One question: What do you mean with cold pull? Should I remove the nozzle and pull a cold filament through the transortation unit?
Change of infill: I already use gyroid infill but I will start printing again showing some pictures here.
Changing the idler perssure will be the next step after having finished the first proposal.
As I already mentioned before I will take some pictures to better explain the priniting results in dependence of the parameters and changes.
RE: Underextrusion and transport problems of the filament
@diem
How can I enclose some pictures. The add media button show any reaction.
RE: Underextrusion and transport problems of the filament
https://help.prusa3d.com/article/cold-pull-31702-core-one-35702-core-one-l_930551
Cheerio,
RE: Underextrusion and transport problems of the filament
Thank you for advice. It's just the prposal made by the 24/7 Hotline. I will continue the discussion with the hotline and after having concluded the issue, I will summarize the findings here, hopefully soon.
The Hotline proposed so far to:
- change in the slicer the nozzle type
- to update the Firmare version
- to carry out the cold pull test
Thanks in advance for your helpfull comments
Bernd


