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Both items were printed at the same time. The item on the right was perfect while the one on the left has crazy thick strings. Sorry I didn't keep the build plate's orientation, you can see how they were positioned in the Cura screen cap.

Photo of two printed models, the left model has stringing while the right one doesn't

Screenshot of the print preview in Cura showing nozzle travels

I thought the stringing was from nozzle travel but if that were true the strings would be coming from the center pillar which they are not. Some of the strings shoot out from the left which doesn't make any sense.

I checked the bottom and it seems like the first layer is perfect or pretty damned close to it.

Sovol Sv01 pro

  • This is similar to an Ender 3 S1
  • direct drive
  • Creality silent board
  • CR touch
  • Marlin 2.0
  • hot end I'm not sure what's in there but it has a V6 nozzle rather than an MK8
  • PEI sheet
  • K value 2.0 - this was the factory setting
  • All the parts are pretty new since I bought the printer on an Amazon Prime day about a month ago.

Settings

  • Inland PETG - Yellow
  • a few days ago it had a 6hr session in a filament dryer
  • 225 °C nozzle
  • 70 °C bed
  • retraction 3.0 mm
  • print speed 60 mm/s
  • print acceleration 500 mm/s
  • jerk 12 mm/s
agarza
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Biclops
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  • The max print speed of the premium quality 2.85 mm PETG I use, is 50 mm/s at higher temperatures you use (240 - 245 °C). I do have a no-name 1.75 mm PETG brand that prints at 230 °C, but that is with an expensive hotend capable of melting the PETG quick enough. You should increase temperature and lower print speed. – 0scar Aug 13 '22 at 08:07
  • Are you using combing with max comb distance with no retract? Is it possible to share the G-code to check? – eskeyaar Aug 19 '22 at 14:34
  • That's not stringing, that is a perimeter line that is missing from the item that was not deposited properly and "dragged" behind the nozzle. Misleveled most likely. – Trish Aug 20 '22 at 13:02

1 Answers1

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225°C is way too cool to print PETG, especially at 60 mm/s if your printer's extruder is similar to the Ender 3's stock extruder (going off what you said; I'm not familiar with your specific printer). It will be having serious trouble extruding, slipping in the filament gear, at which point you'll have too little material, so what does get extruded gets stretched out too thin and is under a lot of tension, and since it's not hot enough to bond well with the previous layer and also not thick enough to press well against the previous layer, it gets pulled across a diagonal rather than following the toolhead path.

Drop your speed for PETG to 30 mm/s or lower and increase the temperature to 235°C at a bare minimum. I would really call 245°C the minimum for PETG, but that's borderline too hot for the stock PTFE-lined heatbreak and will degrate the PTFE (and arguably offgas harmful fumes, although probably at levels way too low to actually be harmful) over time.

R.. GitHub STOP HELPING ICE
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  • I was just using the default settings in Cura. I'll try 235 and 30mm – Biclops Aug 20 '22 at 07:12
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    I did a temp tower and 235 was the best range. It was shiny and it didn't snap off easily. Did a benchy at 235 and 30mm and it was perfect. Thank you. – Biclops Aug 20 '22 at 23:46
  • If you're not too busy I have another PETG question I'd like your input on. https://3dprinting.stackexchange.com/questions/19828/petg-benchy-boogers-and-stringing. Thanks. – Biclops Aug 26 '22 at 05:41