Is Prusa Mk2 extruder food safe?  

Re: Is Prusa Mk2 extruder food safe?

Alex

I believe the answer is technically no. For that I think you require a full stainless steel hot end.

In practice I think that many user print mugs and the like and use them without issue.

There's an interesting article here (thanks Google..): https://all3dp.com/food-safe-3d-printing-material-filament-plastic/

Peter

Re: Is Prusa Mk2 extruder food safe?

Hi PJR,

thanks for your answer.
Do you mean i should use this kind of nozzle?
http://e3d-online.com/E3D-v6/Extra-Nozzles/v6-Extra-Nozzle-Stainless-Steel-1.75mmx0.40mm

Alex 🙂

Re: Is Prusa Mk2 extruder food safe?

Alex

No, not quite. Problem is also with the PTFE tube inside the hot end

But I will qualify all this by saying that I am only mentioning what I think I have read elsewhere; I may be very wrong.

I really think you need to Google something about 3d printing food. And then if you want to get "official" you need to contact some relevant authority (FDA maybe?).

Peter

Re: Is Prusa Mk2 extruder food safe?

... Problem is also with the PTFE tube inside the hot end ...
so a ptfe coated frying pan would be a problem as well ?

➡ i would be more worried about little metal parts, that might grind off from the extruder pulleye.

Re: Is Prusa Mk2 extruder food safe?

Ok, so for now i think i won't print objects that will be used in contact with food 🙄
As i cannot give him food safe full certification (i understand there are too many parts involved in the PLA path, other than the nozzle itself), i will simply make him some nice looking gadgets to show, instead, for room decoration. Maybe for personal home use it would be different, as maybe a certified food safe PLA and a stainless steel nozzle would be enough for seldom use, but i don't know what kind of food or drink will be in contact with these materials in his bar and how many times they will be used 🙁
For now my question has been satisfactorily answered (advices are always welcome, though!) 😀

Alex 🙂

Re: Is Prusa Mk2 extruder food safe?

... Problem is also with the PTFE tube inside the hot end ...
so a ptfe coated frying pan would be a problem as well ?

➡ i would be more worried about little metal parts, that might grind off from the extruder pulleye.

Jeff. Does your frying pan have a "food safe" certification? I would guess it does. Does PTFE tubing manufactured in a back-street shop in a small Chinese village have a "food safe" certification? I doubt it.

And I guess that 3D printers designed for printing food don't have any "little metal parts".

Peter

Re: Is Prusa Mk2 extruder food safe?

so a ptfe coated frying pan would be a problem as well ?
I don't think PTFE tube is problem, but there is quite long filament path in extruder body made of ABS and also there is extruder pulley made of brass, which might contain Pb.
In short - current extruder assembly is definitely NOT food safe.

Re: Is Prusa Mk2 extruder food safe?

➡ by the way, as i was doing some research about the prusa firmware, i noticed a curious little if-clause inside the pins.h file:

#ifdef BARICUDA
#define HEATER_2_PIN 6
#else
#define HEATER_2_PIN -1
#endif // ifdef BARICUDA

💡 and because i didn't know anything about BARICUDA, google gave me a link to this Baricuda Extruder for 3D Printing Sugar and Chocolate.
so i guess it might be possible to compile the prusa firmware with a #define BARICUDA option inside the Configuration_prusa.h.

Re: Is Prusa Mk2 extruder food safe?

Aside from the mechanisms needing to be food safe, keep in mind that they should only be used with food-safe materials. That is, even if you have a food safe extruder, if you print using non-safe materials, to be on the safe side, you shouldn't consider anything printed with it later to be food safe, because the previous plastic will have contaminated the hot end, etc.

In hospitals, they have dedicated printers with stainless steel nozzles and all-metal hot ends that are loaded only with approved materials (e.g. Taulman medical grade nylon).

Pragmatically, I'm not sure how much this is strictly necessary, but hospitals play by the rules, and the rules are strict.

As far as PTFE tubing goes, I wouldn't think that the tubing that doesn't get hot would be an issue, but the BTFE inside a hot end breaks down from the heat (and needs to be replaced periodically) and I can't imagine that the chemicals released in that process would be good for you. That might be why they always have warnings not to over-heat any teflon pan. The E3D v6 PTFE tube is only in the 'cool' end of the extruder, so this shouldn't be an issue for the newer i3's.

Re: Is Prusa Mk2 extruder food safe?

Yeah, i understand what you mean: first i should replace the filament with the food safe one, load it so all the prevoius filament parts are pushed away, then i should replace the brass nozzle with the stainless steel one, then calibrate the Z level, then print the item. And if i want to change again the filament (maybe i want to print with another colour or material) i have to replace again the nozzle (so that there's no contamination between materials), Z level again. I should replace the brass gear that moves the filament, too. Then again the extruder plastic parts are made with ABS, and i should print them with another material that is food safe and resistant to high temperatures (so no food safe PLA, it would melt down).
Too messy for me, now... 😉

Alex 🙂

Re: Is Prusa Mk2 extruder food safe?

2nd printer ? 🙂

Re: Is Prusa Mk2 extruder food safe?

Then again the extruder plastic parts are made with ABS, and i should print them with another material that is food safe and resistant to high temperatures (so no food safe PLA, it would melt down).
You don't have to replace all extruder body. The only part where ABS touches the filament is hole on the top of extruder body leading filament to extruder pulley. Make the hole bigger and insert stainless steel tube into it.

Re: Is Prusa Mk2 extruder food safe?

@JuanV

Maybe the multi extruder kit would be a better (anche cheap) choice, rather than a second printer, in this case 😀
Seriously, i could use 3 extruders for my normal prints and keep the 4th one only for these kind of "special" prints.
I'm planning to buy the kit anyway: i'm starting to experience multi colour printing, but freedom to use these colours is still limited in creativity with only one extruder.

@david.t2

Nice point! Noted 💡

Now, the only questionable part should be PTFE tube inside the hot end 😕

This topic is giving me lots of good ideas 😀

Alex 🙂

Re: Is Prusa Mk2 extruder food safe?

If your food & hygiene laws for commercial bars or restaurants are anywhere near as strict as they are in Germany, I'd stay well away from serving customers anything that came in contact with things out of a hobbyist 3D printer. Inspectors usually have no sense of humor when they suspect a violation.

Re: Is Prusa Mk2 extruder food safe?

Maybe the multi extruder kit would be a better (anche cheap) choice, rather than a second printer, in this case 😀
Seriously, i could use 3 extruders for my normal prints and keep the 4th one only for these kind of "special" prints.
I'm planning to buy the kit anyway: i'm starting to experience multi colour printing, but freedom to use these colours is still limited in creativity with only one extruder.

You do realize that all four filaments feed into the same hotend/nozzle so this would not work.

Re: Is Prusa Mk2 extruder food safe?

@stephan.k

My concern is that what i print is "technically" food safe, i mean, if it's something that i can use for myself then that's good for me.
Then, how he will justify to the authorities these things... it's not my concern. They are gifts i make to a friend of mine in private (and i am not paid for these things.... they are REALLY gifts, maybe some free beers i guess, hehe). I already told him that i cannot make any certification.

@richard.l

Just realized... 😥
Thanks for the clarification, i think i will study better this kit and understand if it can do what I would like 🙂

However, now i am not going to use any of my prints in contact with food until i find a solution, and if it's not possible at all, then... well, i can live with that 😀

Thank you very much,

Alex

Re: Is Prusa Mk2 extruder food safe?

i plan to buy a printer. i could not find with google or on your forum how could i add a chocolate printer facility to i3mk2. my wife does a lot of cakes and it will be fun.

Re: Is Prusa Mk2 extruder food safe?

Yeah, i understand what you mean: first i should replace the filament with the food safe one, load it so all the prevoius filament parts are pushed away, then i should replace the brass nozzle with the stainless steel one, then calibrate the Z level, then print the item. And if i want to change again the filament (maybe i want to print with another colour or material) i have to replace again the nozzle (so that there's no contamination between materials), Z level again. I should replace the brass gear that moves the filament, too. Then again the extruder plastic parts are made with ABS, and i should print them with another material that is food safe and resistant to high temperatures (so no food safe PLA, it would melt down).
Too messy for me, now... 😉

Alex 🙂

no, you need the stainless heat block AND nozzle AND heatbreak. Then printed materials would be single USE.... you cannot thoroughly wash/sanitize a 3d printed part... look under a microscope.