3DPrinting
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: !functionalprint@kbin.social or !functionalprint@fedia.io
There are CAD communities available at: !cad@lemmy.world or !freecad@lemmy.ml
Rules
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No bigotry - including racism, sexism, ableism, homophobia, transphobia, or xenophobia. Code of Conduct.
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Be respectful, especially when disagreeing. Everyone should feel welcome here.
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No porn (NSFW prints are acceptable but must be marked NSFW)
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No Ads / Spamming / Guerrilla Marketing
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Do not create links to reddit
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If you see an issue please flag it
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No guns
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No injury gore posts
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 
Moderation policy: Light, mostly invisible
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PETG is truly a pain!! You'd think with a plastic used in water bottles, it would do better with moisture. I recommend the brand CC3D if you want something reliable (and ultra cheap!) Also remember that PETG needs more room between the nozzle and the build plate (higher z offset) so that the filament doesn't stick to the nozzle and make a mess :)
@galaxi
@zipsglacier
Drying is part of the process when raw plastic pellets are used in injection molding. The only reason it's not more common in 3DP is that common materials like PLA and ABS arent particularly hygroscopic. PETG is slightly more hygroscopic, but materials like TPU, PET, nylons, etc are highly hygroscopic and definitely need drying to print well.
This is one of those pieces of 3DP lore that isn't correct. If Z offset is set accurately, it doesn't need to be changed for any material, but extrusion multiplier/flow does.
The reason why bumping z offset bandaids the problem is because PETs are highly incompressible, i.e., they don't respond well to being squeezed and will displace under pressure. Raising the z offset means you're putting the same amount of material into a larger physical volume. This effectively lowers EM for the first layer, but introduces accuracy issues in the rest of the print.
Instead, it's better to make sure z offset is dead on accurate and then adjust EM down so that flow is correct throughout the print.
Think about what happens to water if it's heated above 100C... it turns into steam! The more water there is in the plastic the more steam there will be, causing the various issues like bubbling. The release of steam also means some of the heat is not being absorbed by the filament, leading to temperature issues as it exits the nozzle