So, yes, I know that due to layer lines etc, FDM (PLA) printing isn’t safe for food, however is there a way of making it safe? Essentially I want to create a draw insert for cutlery, so can I print it, the coat it in something to make it food safe?
So, yes, I know that due to layer lines etc, FDM (PLA) printing isn’t safe for food, however is there a way of making it safe? Essentially I want to create a draw insert for cutlery, so can I print it, the coat it in something to make it food safe?
Others can correct me if I’m wrong, but PLA the plastic itself is food safe. As in, you can put it in your mouth and it’s fine. The issue comes from the 3d printing process which tends to create small pockets and porous surfaces where microbes can hide and grow once it gets wet, kind of like a sponge. So you could print a single-use fork and eat with it, but don’t reuse it later.
I think an insert for cutlery would be fine since you aren’t going to be getting it wet or putting it in contact with your mouth or food.
You are correct, PLA is per definition food safe. The problems you mention are also correct. There are two other major problems: There can be residues from other prints in your printer which contaminates your prints. The manufacturer does not label their filament as food safe. There are no list of additives which could be harmful.
There are ways around some of the problems like smoothing with heat or chemicals. Most of the time it is no major concern. Containers for cutlery? No problem as long you are not selling them. Container for food itself like lunch boxes? This is something I personally would not risk. Lids for containers with no direct contact to the food? I think you should be alright. Just don‘t do it commercially.
I remember reading something that matches exactly what you’re saying above. The material is food-safe, but the geometry is not.
So 3d printing a cup, plate, or measuring cup is not recommended, but the cutlery insert OP is describing should be fine, no need to coat it.