Suddent quality problems

[Andrea Miramonti]

Printer Model

2.4 350mm

Extruder Type

Clockwork 2

Cooling Type

Afterburner

Hi everyone, been printing with my voron 2.4 from more than 1 year now (with regular maintenace).
A few days ago i started to encounter some problems, here you can see a test done some time ago (on the left) and a test done today (on the right).



I used the same filament (PETG) with the same cura slicer profile and parameters.

I did some tests already:
- Change filament spool
- Change cooling fan speed
- Change print temperature
- Lowering print speed
- Increase the chamber fan
- Printing with the doors open

I really can't figure this out, i was thinking at a mechanical problem but nothing seems wrong.

I will attach the printer config and the cura slicer profile.

Any suggestions ?

Thank you in advance.

 

[NoGuru]

I know you said you changed spools but have you tried to dry it?
What about Nozzle change?
Or just cleaning the hotend out in general. If I remember, PETG is not easy on hotends.

Last thing I can think is the extruder might need cleaned or -redone.

One more thing, try a a different slicer.

 

[Andrea Miramonti]

I know you said you changed spools but have you tried to dry it?
What about Nozzle change?
Or just cleaning the hotend out in general. If I remember, PETG is not easy on hotends.

Last thing I can think is the extruder might need cleaned or -redone.

One more thing, try a a different slicer.

Hi,

- Yes, the filament is in a drying box all the time.
- Yes i already tried to swap the nozzle with a new one.

At this point i will try to clean / replace all other hotend parts and examin the extruder.

Ty for the help.

 

[NoGuru]

Is this only with overhangs? Maybe this what needs the focus in the slicer?

 

[stevereno30]

PETG is quite picky.. After printing ABS for the past year, I printed some parts in PETG and was having similar issues. The things that fixed it for me:

-Print slow. Like 50% of ABS speeds at least. I think my max print speeds with PETG are around 60 mm/s. Perimeters are around 40.
-Keep the doors open. Voron print chambers get too hot for PLA (obviously) but are also too hot for PETG.
-Make sure you have sufficient cooling. I usually have my part cooling fan running at a constant 40% speed (GDSTime fan). If your fan is weaker than those in the BOM, you may need to increase this speed.

When printing too fast, PETG will curl at even the slightest overhang. It gets to the point where the nozzle will eventually be dragging through the accumulated curling perimeters, which will eventually lead to skipped steps on larger prints.

 

[Andrea Miramonti]

Is this only with overhangs? Maybe this what needs the focus in the slicer?

Yes, but i am using the same settings that i used for months with no prblems, i honestly don't see how this could be a slicer problem, but i will give prusaslicer a go.

 

[Andrea Miramonti]

PETG is quite picky.. After printing ABS for the past year, I printed some parts in PETG and was having similar issues. The things that fixed it for me:

-Print slow. Like 50% of ABS speeds at least. I think my max print speeds with PETG are around 60 mm/s. Perimeters are around 40.
-Keep the doors open. Voron print chambers get too hot for PLA (obviously) but are also too hot for PETG.
-Make sure you have sufficient cooling. I usually have my part cooling fan running at a constant 40% speed (GDSTime fan). If your fan is weaker than those in the BOM, you may need to increase this speed.

When printing too fast, PETG will curl at even the slightest overhang. It gets to the point where the nozzle will eventually be dragging through the accumulated curling perimeters, which will eventually lead to skipped steps on larger prints.

I am using the same settings that i used for months with no prblems, i already tried lowering speed, printing with the doors open and printing with the part cooling fan at 100%, no improvements.

 

[SputnikRSS]

I have had almost this exact same issue just pop up on my machine. I can no longer print an overhang over 40deg without it curling up and ruining the print. Not sure what has caused it.

Things I have tried.

New filament
Dry current filament
Slower Print speeds
Smaller layer height
Lower print temps
Changed from Afterburner to Stealthburner for better cooling.

All these changes seem to have little to no effect on the overhangs I am currently at a loss.

 

[Andrea Miramonti]

I have had almost this exact same issue just pop up on my machine. I can no longer print an overhang over 40deg without it curling up and ruining the print. Not sure what has caused it.

Things I have tried.

New filament
Dry current filament
Slower Print speeds
Smaller layer height
Lower print temps
Changed from Afterburner to Stealthburner for better cooling.

All these changes seem to have little to no effect on the overhangs I am currently at a loss.

Hi
At the end i was able to fix the problem by replacing all the printed parts of extruder, hotend end part cooling fan support, fortunatly i have another printer capable of printing ABS/ASA, otherwise i would had to buy the replacements.

I noticed that the old component slighly deformed offering the airflow of the part cooling fan a path to escape before arriving at the printed part (or at least thats my thinking).

 

[SputnikRSS]

HMM other than the hot end I have switched over everything already as I moved from Afterburner to Stealthburner so larger fan different body etc. I have pulled off all the panels for cooling as this is even happening with PLA. I also slowed it right down to 35mm/s still no change I am at a loss.

 

[Andrea Miramonti]

HMM other than the hot end I have switched over everything already as I moved from Afterburner to Stealthburner so larger fan different body etc. I have pulled off all the panels for cooling as this is even happening with PLA. I also slowed it right down to 35mm/s still no change I am at a loss.

Surly you have already done the PID calibration but have you checked that the sensors are reporting the right temperature (with a tester maybe) and that the sensors and heaters are set correctly in the firmware ?

 

[SputnikRSS]

Surly you have already done the PID calibration but have you checked that the sensors are reporting the right temperature (with a tester maybe) and that the sensors and heaters are set correctly in the firmware ?

Yep PID was done checked temps with another RTD just incase and all where within 5deg.