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: or !functionalprint@fedia.io
There are CAD communities available at: !cad@lemmy.world or !freecad@lemmy.ml
Rules
-
No bigotry - including racism, sexism, ableism, homophobia, transphobia, or xenophobia. Code of Conduct.
-
Be respectful, especially when disagreeing. Everyone should feel welcome here.
-
No porn (NSFW prints are acceptable but must be marked NSFW)
-
No Ads / Spamming / Guerrilla Marketing
-
Do not create links to reddit
-
If you see an issue please flag it
-
No guns
-
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
can I 3d print PETG objects, use them, put them in the dishwasher, and then safely reuse them?
No.
The glass transition temperature (the temperature where plastic starts to become malleable) of PETG is 85°C, so if you put a PETG spoon in boiling water, it would deform and become pretty useless. However, if you used a high temperature plastic with a glass transition point above 100°C, you might be able to get away with this method.
Also, just to clarify, a dishwasher does not get to 100°C. You could use it to get the initial food off, but you would then need to boil the utensils manually on a stove to actually sterilize them.
You can sanitize at boiling, and far below that too. For actual sterilization, you'd need to be above boiling using something like an autoclave or pressure cooker.
There is no such thing as food safe plastic
Nonoilen filament printing is what you're looking for.
It's a pain to print with and I suggest you just don't print food safe objects.
To even approach food safety you'd need to do the following
- Use a material with a higher glass transition temp than PETG that is also a food safe plastic. You really need to be able to wash in HOT water. I'm not sure if PC blends are food safe, but if they are that might be the way to go.
- Ensure that EVERYTHING in your filament path is food safe. E.g:
- No toxic lubrication in the feeding mechanism
- No possible contamination from other filaments: never use that hot end for anything else.
- The nozzle and meltzone are made of food safe materials with food safe production (many brass things end up contaminated with lead)
- Seal or smooth: Its not just layer lines. As the plastic cools it will form microcrazing (tiny cracks) that serve as an ideal place for bacteria to hide during washing/sanitizing. Even if you use a material that can go in the dishwasher if those cracks are still there you'll still end up loaded with bacteria/fungi/mold.
Now I want to print molds and make carbon fibre cutlery just for shits and giggles.
You could investigate PVB which can be smoothed. It does soften at a low temperature though so you can't cook it or wash it in the dish washer. If it's well smoothed you can wash it with warm water and soap though.