I am trying to get PETG working. I get pimples on one side of my print.
I’ve tried the setting from the support page and this forum post. But I get the same results.
I’m not sure what to try next, or the source of my troubles.
I did do a filament calibration, and that did make things a lot better.
The forum prohibited me from uploading images 
As @WilliamBosacker said, share some pics. Use an image sharing service until you have spent enough time on the forums to be able to upload.
Have you tried drying out your filament? Sounds like this could be the problem, but without seeing pics I’m just guessing.
What temp are you printing at?
-S
I have done some PETG printing recently with PolyLite PETG. Using 240°C for the nozzle and 70°C for the print bed. I sliced everything with 0.3mm, 0.2mm or 0.12mm and would not recommend anything below that. And yes, I have also seen some little “pimples” at the side walls of the print. In my case those occurred because the nozzle caught some already printed material. I have ordered a nickel plated nozzle but it will take another 2 weeks or so until I receive that to share some results. Nickel plating is often used for injection molting due to its non-sticky properties. For some prints I was able to mitigate this issue slightly by enabling z-hops. That, however, creates a lot of stringing. You probably also want to ensure that the filament is dry when printing.
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I live in a hot dry climate (so cal desert).
Putting it in the oven at 150F didn’t seem to help much.
I tried some new setting, but got something that looks a whole lot like a plugged nozzle, but load filament extrudes filament. I do get some warping/sticking to the side of the nozzle.
I can’t seem to find my 2nd print. Don’t worry, turns out it’s easy to make a new one!
Looks like under extrusion?
I calibrated the steps per mm for the extruder? It’s a new nozzle, so it shouldn’t be plugged?
Using a larger layer height helped, for sure.
That looks quite different from the “pimples” I have seen. Therefore, I can give you only little advice here. I would recommend you to check the nozzle and filament quality. The filament should come out straight from the nozzle.
On the side note: I have seen quite inconsistent extrusion with PETG in my prints. The wall thickness variated from 0.3mm to 0.47mm. I am not sure whether this is in any way related to your issue, though. And I am still lost for myself on how to fix that.
P.S.: I print PETG with 50mm/s infill and 40mm/s for the walls/top/bottom.
I’m using Luban.
Luban stores the config in C:\Users<user>\AppData\Roaming\snapmaker-luban\Config\A350 and C:\Users<user>\AppData\Roaming\snapmaker-luban\Config
I did do the filament calibration (Extruder E-steps Calibration (https://teachingtechyt.github.io/calibration.html#esteps) and the bed leveling calibration with the 11x11 grid.
I did not do the PID tuning.
My test prints with PLA worked pretty well and got a good adhesion and consistent thickness with PLA with the squares test.
So, I think I jammed my nozzle with all my fiddling. Filament is coming out super slow and eventually grinds the filament and doesn’t pay out reliably.
I’ll bump up the speeds.
I’ll try the suggested higher speed settings and report back once I get filament flowing at a reasonable rate.
Also, thanks for that post. I’m still trying to work thru it.
When the files are created, they are made with a numeric SN of some form. I just rename them to be useful for me to keep track of. I don’t know why SnapMaker didn’t make this less awkward to keep track of (or if I’m inadvertently breaking something).
There’s also a few settings that aren’t in the UI and UI controls.
material.petg.def.json (1.0 KB)
quality.petg.def.json (3.6 KB)
For sure, don’t edit the file in both locations at the same time.
TL;DR;
Luban doesn’t import export. Luban stores it’s config as JSON objects/files. Manually managing these files, the same effect can be had.
Luban uses JSON to store all the configuration settings. (being a JS/Electron application, it makes sense). Luban does not offer a sane configuration import/export mechanism.
To share configuration settings, take endless screenshots. To exchange settings between machines or installs, you must manually edit all the settings.
or copy some json files.
As the objects in the user space application config directory controls all aspects of visualization, slicing, and material settings, modifying the JSON stored objects in the applications configuration allows configuration management or more granular configuration.
In lieu of an import/export tool, placing/editing configuration file in the user space application configuration directory has the same effect.
Code explication:
from my very quick scan thru the code:
Luban grabs the base config directory via app.getPath(‘userData’), on windows, this defaults to your home dir with AppData\Roaming<app-name><resrouce> where is snapmaker-luban, and is from the ‘Settings’ dictionary which (extends PureComponent).
So, all the config stuff end up in C:\Users<user>\AppData\Roaming\snapmaker-luban\Config
Therefore, if you want something to end up in the Luban configuration space, edit files in that space.
The definition/index manager grab files with the right prefix (‘material’ for materials, and ‘quality’ for slicer settings) with the format ‘definitionId’.‘UUID’.def.json and load that object to do whatever the tool needs to do.
Not doing that to show what the settings are.
I did not receive a cleaning lance or wire in my kit. Is any nozzle cleaning lance that’s less than 0.4 sufficient?
I don’t have any Nylon. My atomic pull/cold pull with the PETG was not successful.
So, in the end, the biggest impact was a defective hot end. The hot end I was using, the thermistor didn’t reach into the block very far. The hot end temp would swing like crazy, and eventually become very hard to push when pushing filament thru the nozzle, but the sm would not read the temperature as constant.
When the temp did change, the nozzle would rocket up, but the thermistor would barley change (some 20°C changes)
So, in the end, 20mm of thermistor wire.
It’s still stringy, and there’s certainly a rougher side and a smoother side, but overall the print is usable.
Also, I didn’t know the SM could go so fast. I really like the speed the prints are progress at.
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I like these settings. It gives a respectable print speed.
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The nozzle arrived and I did some tests. I cannot measure any change in the flow rate or dimensional accuracy or the like. Nor can I see a difference in the surface quality. Yes, the nickel plating makes the nozzle stick less to the molten filament, but not that much. There is hardly any difference on a long run print. So not sure if such nozzle really adds any benefit with PETG given the price difference.