Hello! I’d like to print food safe objects to use in the kitchen, like spoons and glasses and so on. Looking on the web it seems that the problem with 3d printed objects is that the space between layers is like bacteria’s heaven, so after one use you have to throw them away. The only way I found on the web is “coat with resin”, but I don’t like this very much, as scratches can remove the coating. also “print a negative and use it like a stamp” seems like too much work for a simple spoon.
so the question is, what if I use a filament that can go into the dishwasher, so I can clean it with boiling water? the web didn’t help me much on this, as I found different opinions on the matter: some people said that PETG could go in the dishwasher, some said no.
what is the real answer? can I 3d print PETG objects, use them, put them in the dishwasher, and then safely reuse them?
I’ve never tried petg in the dishwasher, I’d guess I’d probably deform something thin, but I don’t know. Putting it in the dishwasher won’t be enough to clean it though, you’d need to boil it for a while. A dishwasher won’t get hot enough to kill the bacteria growing in the recesses.
Most 3d printed materials, including petg, won’t have a glass point high enough to boil them.You’d need to keep it in boiling water long enough to raise the temperature of the innermost recesses. Basically, there isn’t any good resource for food safe 3d printing because it’s just not worth the effort.
If you do want to do it, you’d need to make sure: you have food safe filament that can withstand boiling temperature without softening, your printer can get hot enough to print that filament, your print head/nozzle is made out of food safe components, and you boil it for a while after every use.
Resin coating can lower the temperature requirements because of being able to clean it normally. But you still need to make sure you have food safe filament and print head.
Some dishwashers do get hot enough, having options specifically for sanitizing during a cycle. It’s essentially Pasteurization which factors in not just temperature, but also time. While flash Pasteurization requires high temperature, longer times at lower temperatures can effectively kill harmful microorganisms.
That’s what soap is for. It’s no worse than any plastic bowl or whatever you use, scratch, and put in the dishwasher.
Nah 3d prints are porous, so it’s basically impossible to properly clean them by washing.
Thanks for the detailed answer! I have to give up then :(