this post was submitted on 28 Nov 2025
20 points (100.0% liked)

3DPrinting

21995 readers
82 users here now

3DPrinting is a place where makers of all skill levels and walks of life can learn about and discuss 3D printing and development of 3D printed parts and devices.

The r/functionalprint community is now located at: or !functionalprint@fedia.io

There are CAD communities available at: !cad@lemmy.world or !freecad@lemmy.ml

Rules

If you need an easy way to host pictures, https://catbox.moe/ may be an option. Be ethical about what you post and donate if you are able or use this a lot. It is just an individual hosting content, not a company. The image embedding syntax for Lemmy is ![](URL)

Moderation policy: Light, mostly invisible

founded 2 years ago
MODERATORS
j4k3@lemmy.world
andypiper@lemmy.world
GrayBackgroundMusic@lemmy.zip
20
I'm doing something wrong; can't print this PETG (imgur.com)
submitted 3 months ago* (last edited 3 months ago) by csm10495@sh.itjust.works to c/3dprinting@lemmy.world
28 comments fedilink hide all child comments
 

I have this PETG; its Kingroon Blue PETG. I can't get it to print nicely no matter what I do. Been testing with benchy over and over.

The filament is as dry as I can make it. It's been in the dryer for at least 12 hours before each print. I even have tried snipping the part of the filament not in the dryer to start from a dried state. The Relative Humidity doesn't drop anymore at this point (from 19ish).

I've tried different temperatures from 220 to 260. I've tried different retraction lengths and speeds. I've tried with the cooling fan on/off and at a couple middling percentages. Also different speeds from 30mm/s to 45 to 60.

I tried printing a retraction tower and it fell apart after the first level.

The first layer prints more/less fine, then eventually it either just falls apart (most of the time) or produces something in awful quality.

I've attached images of everything I can think of from the way it looks on the first layer, to the case where its a benchy out of a horror film, to when it just fails miserably.

Printer Elegoo Neptune 3 Plus. .4mm nozzle (i've tried both copper and hardened steel). Besides the nozzle its stock. If I swap to PLA it prints generally fine.

I feel like I'm missing something obvious. Everyone says dry the filament, but I can't dry it anymore 😢 .

Thanks folks (and if you celebrate: Happy Turkey Day!)

you are viewing a single comment's thread
view the rest of the comments
[–] CrazyLikeGollum@lemmy.world 3 points 3 months ago (1 children)

How can you tell it's under extruded?

@PostnataleAbtreibung@lemmy.world said the same thing in an earlier comment.

If there's some clear sign of under extrusion it might be useful for my reference doc I use when trying to troubleshoot failed prints.

[–] IMALlama@lemmy.world 6 points 3 months ago

How can you tell it’s under extruded?

IMO this is the same as any other hobby. Print enough and you're likely to run into under extrusion at some point. Similarly, I can tell if doughs and batters needs more liquid or more flower by look and touch thanks to making a ton of pizza crusts and pancakes.

If there’s some clear sign of under extrusion it might be useful for my reference doc I use when trying to troubleshoot failed prints.

The first photo in the album looks like 'classic' under extrusion. The layer lines are largely intact, but way less material that is necessary for a solid print is present. The print has better and worse areas, which usually indicates a clog. Combine this with the fact that PETG will clog if you use too much retraction and a user that's new to PETG and retraction seems like a good place to start troubleshooting.

As for helping your guide, simplify3d hasn't been a 'cool' slicer in quite some time but they have a decent print quality guide that names a bunch of failure modes. Ellis' print tuning guide is the best one I've come across.