Hey all,

I normally print my PETG as solid parts, but lately I have been making eNable arms with PETG and see this nasty spidery stuff and massive goo build-up on my nozzle. I am printing such that the nozzle NEVER crosses the open space, but stays on the rims. Even where the head does cross open space because there are curves in the sides, there is no stringing.
Can anyone tell me where this stringing comes from? Perhaps how to stop it? Because I tell the slicers to not retract unless crossing open space, there are pretty much no retracts during 95% of the build. With PLA, this works beautifully, with PETG, not so much.

I am open to advice.
I have tried
I have tried changing retract distance, for obvious reasons, that doesn't do anything.
I tried lowering temperature, but that had no effect and I am concerned about layer bonding.

I am considering
I have coasting enabled, but maybe I need to coast longer? Kind of afraid of gaps and bonding again with this one.
Maybe I should encourage retracts at every layer change so that triggers retracts, wiping and coasting? That seems dicey, but...
Reduce extrusion rate? My solid prints are perfect, no blobbing and a good shiny surface smoothness, so that doesn't seem an obvious choice.

Other stuff?
DLC

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Kits: Folgertech Kossel 2020 upgraded E3Dv6, Tevo Tarantula enhanced parts and dual-head, TronXY X5SA Pro(E3DHemera).
Scratch: Maker-Beam XL Micro Delta, 220x220CoreXY.
Actually bought: Bambu Labs X1 Carbon

Wow. That's bad. It may not be crossing open space but what im guessing is that maybe you're over extruding and the extra melted filament is being pulled into the open space while it's printing the perimeter walls. Try backing down your extrusion amount and maybe the print speed as well. Watch it while it's printing to see exactly when it happens, don't walk away from it.

Try printing slower. I'll regularly print PLA and PLA+ at 60-80mm/s, but when I print with PETG I get those strings at those speeds. It does better at 15-30mm/s.

Good points. There are lots of suggestions out there to print PETG, and they are mutually exclusive. Some say, no fan, some say 100% part fan. Some say drop the temperature, some say run it near the high end. I have been experimenting all over the board to see what my system likes.
Speed seems to be a big deal, retraction seems to be a very big deal. Need to retract more and faster helps, will see if speed drops help too.

Thanks,

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Kits: Folgertech Kossel 2020 upgraded E3Dv6, Tevo Tarantula enhanced parts and dual-head, TronXY X5SA Pro(E3DHemera).
Scratch: Maker-Beam XL Micro Delta, 220x220CoreXY.
Actually bought: Bambu Labs X1 Carbon

I print a lot of PETG. PETG requires exact extrusion, and the only way I was able to print it good was to dump the MK8 direct drive extruder and replace it with a Bondtech dual drive combined with Slice Engineering's Mosquito hot end. What a difference this made. My PETG prints are now stringless, however I still have slight globbing but I have been tuning that out also. This is what made a difference for me. From my expermintation it seems that PETG expands slightly as it is heated and thus the tendency to overextrude.

hope this helps.