Using food ovens for drying filament
I have several high-temp filaments (PET-CF, PA-CF, etc.) that are really difficult or near impossible to dry in regular filament dryers due to their max temperature being too low. However, I have a countertop electric convection oven that can easily do these temps. Thing is, I use it for food, and I am afraid these filaments might contaminate these ovens and I could poison myself if I cook food in them afterwards. I know for example that doing with ABS would be outright deadly. However, some other filaments might be benign and okay to dry in food ovens because they don't outgas anything dangerous.
However, since I'm not sure about it and I can't find any definitive info, I am thinking of maybe I could construct some kind of box with a membrane that allows moisture out, but blocks any volatile compounds from escaping into the oven? Something like the 3M particle/vapor filters used on respirators? I am not entirely sure if they would block anything dangerous and also let moisture out of the box.
Or perhaps the box is not needed at all? Do PET-CF and PA-CF outgas anything that could contaminate food at 100-120°C?
I know it might be easy to say "just don't risk it, buy another oven", but I can't afford the space. And I exhausted all other options for drying filaments. So I'd rather find out for sure if this is dangerous or safe, or if it can be made safe. Looking forward to your comments!
RE: Using food ovens for drying filament
The 3M style filter all have one way valves that need a pressure differential to flow gas, they work on the basis of reduced pressure in the mask from breathing in allowing air in through the filter, then a separate unfiltered one way valve letting it out when you breath out. Therefore to get it to work you would need something to force air circulation. But as they are made out of cheap plastic (because they don't need to be any better) they would themselves melt.
RE: Using food ovens for drying filament
The 3M style filter all have one way valves that need a pressure differential to flow gas, they work on the basis of reduced pressure in the mask from breathing in allowing air in through the filter, then a separate unfiltered one way valve letting it out when you breath out. Therefore to get it to work you would need something to force air circulation. But as they are made out of cheap plastic (because they don't need to be any better) they would themselves melt.
Understood, that makes sense. While waiting for a reply, I found out that these temperatures are below the HDT of each of these plastics, and they don't outgas anything below HDT. So maybe that filter is not needed. However, it is still unclear if filler (CF) releases any particles into the air at these temperatures, and if they need/can be filtered somehow.