At the risk of getting flamed again, here’s a stupid noob type question.
I ran about 500g of the black filament that came with the snapmaker of about 20 prints getting the setting zeroed in. No clogs, no jams, multiple times putting the filament in and out for various reasons.
Bought some True Food Safe PLA from Filaments.ca (TRUE Food Safe PLA - Eggshell White - 1.75mm - 1 KG | Filaments.ca) in eggshell white. Removed the black filament and loaded the white filament. Ran a couple of prints after extruding about 2 meters of filament to remove residual black color. No clogs, no jams, no issues with printing.
I’m still finding black discoloration in the what ever I print.
Maybe this is a hot take that no one else agrees with but I was of the understanding that PLA is not food safe not because of its composition or manufacturing (PLA is classified as “generally regarded as food safe”) but because of its permeability and the FFF printing process introducing porosity. Food particles and bacteria will embed in the material and it’s impossible to clean.
Anyways
Have you heard of cleaning filament? It should do what you want. There’s some on amazon for like $12
Never had this problem changing filaments.
Check that there isn’t any ground up pieces of black sticking to the feeder gears or anywhere inside the head. Blow it out with canned air.
Maybe run it a little hotter for a little while while loading?
You could also swap out the hot end with the spare.
As far as food safe goes I think that a lot of that is dependent upon your usage. How long in contact? Multiple uses? Type of food? Also different for personal use vs. if you were using it commercially and dealing with liability. There’s also food safe as far as the actual material and food safe as far as sanitizing.
Thanks, I’ll take a look at the cleaning filament. I’ve been back and forth on food contact PLA, this is something that will be used only in the dishwasher, and stored in a cleaning solution, so it should work until I’m able to get enough $$ to get an injection mold done. My main concern, besides bacteria and imbedded particles is leaching toxins into the dishwater.
PLA will warp if it gets too hot. The sanitize cycle on a dishwasher is likely “too hot”. I left some objects in my car during the summer, and they warped pretty bad. There are some “high temp” PLAs, but they’re not much higher temp. PETG looks like it’ll stand up to the dishwasher (and car) better, but it’s harder to work with. ABS also stands up better, and can be smoothed with acetone.
PLA is (mostly) made from corn starch / cellulose. It is enzymatically converted to longer chain molecules, but the source is safe to eat. I’m not worried about PLA any more than any other plastic that comes into contact with my food.
The cleaning solution may or may not be a problem, depending on what you use. Dilute bleach should be fine. StarSan, PBW, and BLC might not. The homebrew forums seem to think StarSan is fine. Give it a try, if one of them melts the part, just print a new one. I’d give it a good long soak though, since those methods sanitize after all debris is physically removed.
Acetone doesn’t work on PETG. Only on ABS. You can use a number of solvents, primarily methyl ethyl ketone, but most of them, like MEK, are pretty nasty stuff.
PBW and BLC remove organics. StarSan, Saniclean, iodphor etc. only sanitize clean surfaces. With home brewing you generally use them in conjunction. Remove organisms and then sanitize. Not sure how any of them would interact with either PLA or PETG.
Thanks all. This particular PLA is supposed to be heat resistant to 90C when tempered. Company claims its dishwasher safe. I’ll do some experiments with the StarSan and see what happens.
Thanks for the correction on the PETG / ABS smoothing. I’ll edit my post. I’ve read a bit about the MLK stuff for smoothing PETG, and that’s the closest I’ll get to the process.
@gwfami that means there was buildup on the interior face of the nozzle, and it hasn’t gone away, just got replaced with the new color. You’re probably going to have a major clog soon.
I’d give it a good long soak though, since those methods sanitize after all debris is physically removed.