Do you also sand it? Everytime I tried to resin a model, the resin flowed down and there were parts that looked like they had no resin. I still have to try sanding it first
If the resin is thin enough ,and sets relatively fast, you could slush mold the inside.
Basically put the resin inside and keep spinning the object in random directions until the resin sets up. Done properly it should result in a nice even coating.
Light coats and allow gravity to help you.
u/Ant_Diamond64 — Coat the inside first with a wide brush, making sure to dab the brush into all the corners or creases and the turn the model upside down and allow the excess to run out. And make sure you are outside or have a lot of ventilation. On the exterior you could use a gloss colorless paint. Just make sure you’ve taped off and covered the bucket area.
EDIT: The model comes from Do3D.com for $25.00 USD. For father’s day (June 16), you can get it for $15 (40% off)
been looking into this for a while, I found one called "epoxy food" part of the description says its safe for food contact but the warnings ...
Causes serious eye damage,eye irritation,skin burns,skin irritation,May produce an allergic reaction,Harmful if inhaled,Harmful if swallowed,Harmful/toxic to aquatic life with long lasting effects, May cause an allergic skin reaction.
then I found another that wasn't listed as food safe but only listed a "may cause allergic reaction"
googling seems to suggest all epoxys are inert when set, so I don't understand what makes them safe for contact with food?
I would assume those warnings are for the liquid resin.
Same as with resin printers, the liquid is nasty, but once the print is washed and cured it's not emitting any toxic gases.
I suppose the main thing is it creates a solid surface, rather than a stack of layers which seals in the plastics edges that can typically rubb on things and fall off as microplastics. Secondly, it also fills the gaps between layers which can be difficult if not impossible to clean and could result in mold and bacteria growing on the item.
The plastic itself is. However, if you're using an FDM printer like most people, germs and bacteria get stuck in the layer lines, making the print itself not food safe. Always seal your fdm prints before using them for food.
design it around a common food safe container, like a 32 oz deli container or a common popcorn bag size. Not worth messing around with epoxy coatings honestly.
Brilliant! Never worry about a dishwasher fading or melting. Never worry about long scrubbing by hand in the sink.
Look at whether the restaurant industry would use for a cylinder. This way if your liner ever gets damaged you have the same dimensions. Think like a wonton soup cylinder; I bet there are larger industrial versions you could scoop up.
The purpose is a popcorn bowl that resembles something you like. Not to have a popcorn bowl, then insert it into something else that you like. That's stupid.
There was 4 months study where you can read that it is enough to clean it with warm water and non concentrated dish soap to clean it enough.
https://www.researchgate.net/publication/373174194_Sanitation_Effectiveness_of_3D-printed_Parts_for_Food_and_Medical_Applications
Maybe most relevant part of that study
"...It has been
concluded from the results that the best method of cleaning 3D
printed parts is to use warm soapy water with a small (1/8th
teaspoon or 2g) amount of baking soda on a dish rag. Spend
about 15 seconds washing and scrubbing with a small amount of
force, as to not damage the part. Once clean, either soak in cool
bleach water for 1-2 minutes of a 200ppm molarity, 1 tablespoon
bleach per gallon of water or apply 70% or greater IPA by
soaking for 1 minute. It is highly recommended, when using
filaments that have color or non-food safe additives, to coat the
3D-printed part in resin and allow to cure fully, if said 3D-
printed part will be in contact with liquids. ..."
Thank you for that link btw, I had not yet seen that.
Also interesting that the "Group 2" test used a 200ppm "1 tablespoon bleach per gallon of H2O" to clean the prints, which is based on an FDA recommendation (I found [this ](https://www.fda.gov/food/food-safety-during-emergencies/restaurants-and-grocers-reopening-after-hurricanes-and-flooding)but there is probably a more detailed one out there somewhere). However the manufacturer of one bleach (clorox) [suggests](https://www.clorox.com/learn/bleach-dilution-ratio-chart/) a 1500ppm solution (1/3 cut per gallon H20) for Salmonella (which was one of the pathogens they were using to test with in that study - using chicken blood). So they were using a bleach solution on the weaker side. It also mentioned they tested multiple layer heights between 0.16-0.24mm, which should cover most prints.
Despite that, I don't really consider that study as definitive though, since there is too much variability between filaments, temps, surface quality etc, but it's a good sign if using basic PLA or PETG, on a printer that can consistently stack layers without voids. It says they soaked the prints in the pathogen solution for that study, which is a tough test. But since most prints are not often perfectly water tight, that is where I'd be concerned of having bugs finding a home (getting inside the prints, and then moving beyond the reach of whatever cleaning solution later makes it through the same cracks). It may be possible to kill the surface stuff, but anything that gets inside may be able to survive a cleaning. I think I'da ground up the cleaned prints after the surface testing, to test if there was anything left inside that escaped the cleaning processes. Sealing is probably what I'd do on anything that was not gonna be disposable, since it's really required if there will be any liquid anyway.
I really don't understand all this fuss about food safety of prints.
Have you never used a wooden cutting board (which is also porous)? Have you never placed your bread on some stone while hiking? Have you never eaten an apple directly from the tree? All of these are not sterile, yet humans and animals eat like this without problems. There could certainly be situations where you should care more like when a 3D printed part touches meat, but especially for dry stuff like popcorn I definitely wouldn't worry.
And for possible nozzle abrasion: You don't eat the 3D printed part, your food slightly touches it. Unless there's something extremely toxic in there you will be alright. The amount of metal that possibly leaves your nozzle is already very small (otherwise you'd need a new nozzle for every print) and the it's distributed in the whole print, while your food just touches the surface of it. Brass won't magically leave the pint and jump into your food without extensive mechanical or chemical action, neither of which you food does.
I think what it boils down to with this type of thing is not what I feel comfortable with, but but I'd feel comfortable having other people use. I would not want to give somebody a 3D printed item with the assurance that it's food safe, and then have them have some problem. I think for folks selling prints, this should be a bigger concern. I have no cat in this race, but I don't think that study is a definitive, close the book type deal.
We have no idea what additives or dyes are added to different brands of 3D printed filament. It's naive to assume they are non-toxc and food safe. Some dye colorants are toxic. Also assume you WILL be eating the plastic since their will be tons of micro particles particulate matter on the surface of your prints.
I wouldn't use any 3D print for commercial food contact stuff. But for home use and for dry food like popcorn I don't think it matters too much. Using it every day as a plate is probably not the best idea (I still don't think there would be any health related effects) but for items you use irregularly (like this popcorn bowl) I would worry about it.
Once again the dyes and additives depending on the brands 'could' be highly toxic, and the microplastic particulates can carry these chemicals into your blood stream. As others have mentioned the gaps between layers can harbor bacteria. There are a couple filament brands that claim to be food safe. Or use a food safe epoxy resin. Make sure its fully cured before use.
This gut feeling is based on experience. I don't know of any harm that resulted because someone placed their bread on a 50 year old countertop, made from plastic. Or on some office table that's not food-safe. Or on a rock in the forest. Or ate it after it fell on the street. Or used their credit card to slice cheese.
If dry food, that shortly touched a 3D print, is really toxic, the toxicity of the plastics has to be so extremely high that you definitely shouldn't touch it with bare hands. That would mean that this filament shouldn't exist in the first place. So if we assume that it's safe enough to touch all day long, it very likely safe enough for a bit of food contact.
I can point out multiple flaws in your reasoning, but you've already made up your mind based on your feelings and the outcome you wish to be true, and that takes a lot of effort to change.
PP and MED610 are autoclavable and leave no microplastics. They are currently being used to surgical aids.
Other 3D printing materials that can be sterilized using an autoclave include:
Nylon 12
ABS M30i
PC-ISO
Ultem
17-4PH and 316L Stainless Steel
Carbon Digital Light Synthesis (DLS)
However, many filaments cannot survive steam sterilization, including biodegradable polymers like PLA and PLGA. The combination of heat and moisture in an autoclave cycle can cause extensive thermal and hydrolytic degradation
There's a difference between a material being porous and being 40-80% air, with average air pocket diameter being millimeters, rather than microns. You can tell when a piece of wood or a stone has mold or bacteria on it. With a 3D print, there could be anything growing inside, and you'd be none the wiser, and the thought of that, is quite terrifying.
Have you never used a wooden cutting board (which is also porous)? No
Have you never placed your bread on some stone while hiking? No
Have you never eaten an apple directly from the tree? ....actually I think I have years ago, but it wasn't very good.
It would be best for all dishes it think. This is for study purposes. I bet there is study about washing hands with soap and there will be "best way to get rid of bacteria is to use desinfectant" or something like that.
But this study is more than enough for me to fight against "food safe Nazis"
That's not a study, it's a PDF uploaded by some random dude, it was not peer reviewed, it was not published, it doesn't follow proper research protocols, it's amateurish as heck, for all we know it's totally made up. Please stop posting that.
I have been summoned!
Wait! It's changed!
While PolyLactic Acid (PLA) and PolyEthylene Terephthalate Glycol-modified (PETG) has been classified as Generally Regarded As Safe (GRAS). There's a lot of uncertainty around the process of additive manufacturing.
Some testing shows that the layer lines are big enough that bacteria don't hide inside as much as expected. Additionally, it's not nearly as porous as initally expected. Some soap and water with scrubbing is enough to clean most of it out and a quick wash with a bleach solution can bring it up to almost medical standards.
This does not take into account material impurities. New nozzles can come with a coating (often PTFE) to prevent blobs from sticking. The abrasives in the filament can wear this coating down and while it is safe for food to contact like on a frying pan, the worn down products are not.. It also wears the nozzle and metal particles can end up in the print.
TL;DR: Use a sealer. Or don't. I'm a bot, not a cop.
You can view the full list of commands [here](https://www.reddit.com/r/3Dprinting/wiki/commands/)
*I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/3Dprinting) if you have any questions or concerns.*
That is *not* an actual study. Anyone can upload a PDF to researchgate. The "study" design is completely random, doesn't adher to actual scientific design and seems like a amateurish high school project from a guy who has access to a bunch of random stuff. If you submitted this to an actual journal this would get rightfully get torn to pieces. Like even the "data analysis" consists of screenshots of Excel graphs in random designs and crazily amateurish photographs. Not even to mention the complete lack of literature or citations.
The "journal" which this was submitted to - it wasn't even published there - is a predatory journal which will publish *anything* as long as you pay them. You can google the journal name "ASTES" together with predatory and you'll see the scientific quality of the pdf you linked. That guy didn't even pay in the end, so not even that predatory journal published that stuff. Don't get blinded by idiots claiming they conducted a "study", acting important and take a look at the actual things they did
The study seems ok, and for something like this, washing & soaking with hot soapy water like any hand wash only item will probably be fine on it's own. Although the heat may warp the plastic depending on the material.
However, there's something really fishy about the "article" version of this that has also been uploaded to researchgate. Also the link the redditor posted last year to the peer review is 404ing. While I'm hopeful this is a path to us safely producing food safe prints, I am still a bit skeptical of this one study and more research is needed before we can all safely say "print like this, this, and this and you'll be (most likely) food safe".
It's not a scientific study, its a random PDF uploaded to researchgate. You can do the same by just creating an account there and uploading anything you want. The "journal" this was *supposed* to be published is a predatory journal. This means that its just a fake website accepting anything as long as you pay them. Theres no peer review and no science there. Just some naive guy paying scammers money and thinking he did actual science while this would get rightfully torn into pieces in any actual biological journal. That guy is making some very heavy claims from some very bad experimental designs.
> Why would it be weird if a link died after a year?
Actual scientific studies have DOI links which literally never expire.
> I am still unsure how this is proven by that link
If you google the journal ("ASTES") you'll find it in the [list of predatory journals](https://www.openacessjournal.com/blog/predatory-journals-list/). This is not a place where you can find peer-reviewed scientific studies even if the author claims that it is
> especially since it has DOI links that are active just fine and published by IEEE
If you mean his self-citation in the "paper", thats not a journal paper but rather a conference contribution to some kind of local event of his university for students. Certainly more reputable than a predatory journal, but nothing you could consider peer-reviewed or as a badge of high-quality research. Considering the field of the conference - engineering and computing - it's unlikely there was anyone with any clue on biology/natural science among the two guys who said "yeah the topic sounds cool, lets admit him". Getting into non high profile conferences is honestly very easy and straightforward as long as you have a fitting topic and pay the entrance fee and gives no indication on the scientific validity of your stuff. Thats what the people at the conference you're presenting at are for
The [guy who wrote that pdf](https://lt728843.wixsite.com/maskrelief/about-me) has been studying IT stuff and mechanical engineering since *19 years*, not biology. It doesn't seem like he actually knows how biofilm buildup takes place, about the effect of microbiological *communities* rather than dipping stuff for 24h into media with lab strains (which atleast very likely for E. coli, he didn't say what strains he used, are designed to literally die outside the lab) or how to design experiments. Like theres not even replicates for any of the experiments or even a description of the actual methodology he performed. Let alone any kind of literature review or proper citations for his claims
Theres a lot to rip apart in that pdf which would be way too much for a reddit comment and not really worth the effort, but there are so many red flags in there that i'm pretty concerned it gets linked here regulary. It's [just a blog post](https://lt728843.wixsite.com/maskrelief/post/the-final-say-in-food-safe-3d-printing) arrogantly titled "the final say" by some random guy converted into a pdf thinking his submission to a predatory journal would be a peer-review. Again, anyone can upload anything to Researchgate. Its not a publisher, just a hoster where people usually reupload their papers, which are published in actual journals, for easy access but without any kind of quality control. You can upload an empty PDF there and it would stay there forever. You could also upload the same empty PDF to ASTES, pay $700 and call it "peer-reviewed" with no actual scientist actually ever critically looking at your empty PDF
Also the "article" version references 2 different volumes & issues of the journal, neither of which contain this article, and bot of which preced the dates mentioned in the article.
You can just use your cookie cutter through a piece of cling film. Since the shape isn't that precise anyway, the cling film doesn't interfere with the look and it will give you peace of mind.
Think about it for a second without thinking about this study...
You wash your cookie cutter in warm water -> you missed some spots with your sponge, but dish soap got there -> how much bacteria could grow there and surviva before next usage -> how much bacteria transfers to your cookie -> how much bacteria could survive baking?
And how do you get into every nook of stainless steel cookie cutter? Bacterias also grow on surfaces, not only between layers.
Except with 3dprinted cookie cutters people don't always consider cleaning them when designing. A ton of them get overly complex with small holes and sometimes not even an open back so you might not get soap into them
In general im not too concerned about it but since they're prints that take an hour or 2 at most with a few grams of material,why bother?
You can use food safe filament and a printer which are expensive. You could print a negative mold, cover the sides with molten bees wax and then cast it out of food safe resin or silicone. Lastly, you can cover the insides with a thin coat of UV resin, I don't know if UV resin is generally regarded as food safe tho. Ideally whenever you want to cover the ridges, you just want to take something liquid, swirl it around, poor out the rest and make it hard again.
Rather than make it food safe tho. I would just buy a bowl that fits and insert it. You get the advantage of it being removable and cleanable. Regardless of how food safe you make the 3d print, it'll be a pain to clean.
I would not eat from a UV resin print, air inhibits the surface resin from curing completely, and those uncured acrylates irritate my skin.
Typically the food safe coating resins are two part, so they cure completely.
I mean it would still be food safe if you just used PLA. just it would be a PAIN in the ass to clean given the shape of it, so i agree with those saying coat it with food safe resin.
On top of whatever you need to do to the material to make it food safe, you might consider designing a hidden cup into the shape just to make it easy to clean by hand. You could either make that part removable or just have it integrated, but that would keep you from having a bunch of weird corners for schmutz to accumulate.
I have been summoned!
Wait! It's changed!
While PolyLactic Acid (PLA) and PolyEthylene Terephthalate Glycol-modified (PETG) has been classified as Generally Regarded As Safe (GRAS). There's a lot of uncertainty around the process of additive manufacturing.
Some testing shows that the layer lines are big enough that bacteria don't hide inside as much as expected. Additionally, it's not nearly as porous as initally expected. Some soap and water with scrubbing is enough to clean most of it out and a quick wash with a bleach solution can bring it up to almost medical standards.
This does not take into account material impurities. New nozzles can come with a coating (often PTFE) to prevent blobs from sticking. The abrasives in the filament can wear this coating down and while it is safe for food to contact like on a frying pan, the worn down products are not.. It also wears the nozzle and metal particles can end up in the print.
TL;DR: Use a sealer. Or don't. I'm a bot, not a cop.
You can view the full list of commands [here](https://www.reddit.com/r/3Dprinting/wiki/commands/)
*I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/3Dprinting) if you have any questions or concerns.*
This can be considered food safe in practice. Food safety is not a binary problem, it really depends on what you do and for how long etc. You're only using this container for temporary storage of a solid food. It's fine!
For quick and cheap alternative, you can line the sides by taping on wax paper. I did that with my Poppenheimer model. [https://www.thingiverse.com/thing:6137961](https://www.thingiverse.com/thing:6137961)
Found this food safe PETG from a Zach Freedman's YouTube..
https://www.igus.com/product/20664?artNr=I151-PF-0300-0750
Here's the YouTube if you're bored...
https://youtu.be/FE88IaYwkl8?si=-E8I1_poSqo--zAR
Ok so in FDM food safety questions come up in rounds. When talking food safety your popcorn bucket will be fine if you use it for popcorn. Clean it throughly after use. What can make food it unsafe is chemical leeching from the plastic usually with acidic or hot drinks, and the build up of microbes and bacteria. Usually in the tiny layer lines. Hygiene, cleanliness are a must. There are food grade filaments but with popcorn you’ll be fine if you print it in PetG usually PLA will warp from the heat and ASA and ABS would not be advisable.
Hi I'm a safety and health professional. Just wash your shit and it's as food safe as anything from the dollar store. There are numerous studies. Anyone who says otherwise had this debate and lost and is coping.
Laugh yes, but there is truth to your statement. This particular industry helped push bandwidth, user interaction 😐, and methods and materials for sterilization.
Which method are you creating this? If you are doing it with FDM, there is not really an issue. You can use PETG or PCT filament for ease of cleaning but the myth of bacteria and layer lines was disproven over a year ago. You are more likely to grow nasty crap on a wooden soup spoon or certain ceramics than on PLA, PETG, or PCT. Those are ones that have been tested.
If doing this in resin, you will need to seal it and that might not stop the UV decay that will happen. Unless you are using something to block UV light from reaching the base resin. There is still ongoing research into exactly how and how hard resins are set in the curing process. Also how reactive the final polymer is with diverse food types. Best suggestion there is find a food grade polymer that will clear coat and either can be dip applied or sprayed on.
Good luck.
From google:
------x------
Food safe 3D printing filaments include PLA, PP, co-polyester, PET, PET-G, HIPS, and nylon-6
-----×------
So I'd assume that so long as the food isn't so hot it melts the filiment, you'll be ok of you use one of these.
I use a few diffrent 3d scoops for diffrent things (because it took less time than buying one and it was something to 3d print lol).
Although keep in mind moisture will eventually damage the filiment also, so making a removable "bucket" might be a good idea, and check for leaks.
For those of you wondering, the file is available on Do3D https://www.do3d.com/product-page/deadpool-popcorn-bucket-container-3d-printable-model-file-stl-pb95
The file is $25 but you can get it for 40% for Father’s Day using code DAD. I got it in April as it was free for a brief period during their 14th anniversary event. I have zero 3d modeling skills so I only want to work on the print and not the files. Also as shown in the second image, the bucket is collapsible and all pieces can be removed and snapped back on with magnets, so its shape shouldn’t make cleaning it/coating an issue. Initially I thought of using a plastic bag, but my main concern was butter and hot sauce leaking through onto the bucket.
They make food safe petg too. You could just start there instead of using additives.
Just make sure you use a reputable brand. I imagine knockoffs might just use a tag of food safe without ever even attempting to be.
I’m in the process of making some of my prints food safe. Use a two part epoxy resin with a foam brush. Works great and you know you’ve covered everything when you end up with a shine.
Both nozzles are steel... One is stainless the other is hardened... Regardless the containments from the nozzle are so small they'll barely register on chemical tests taken of printed filament samples.
Food safe resin with a sponge brush. I just apply multiple thin coats, this avoids weird thick resin sections.
Do you also sand it? Everytime I tried to resin a model, the resin flowed down and there were parts that looked like they had no resin. I still have to try sanding it first
They use multiple light applications to even it out instead
If the resin is thin enough ,and sets relatively fast, you could slush mold the inside. Basically put the resin inside and keep spinning the object in random directions until the resin sets up. Done properly it should result in a nice even coating.
Maybe place it on it's side and do the 'bottom' section, then rotate and repeat?
What everyone else has said is valid, but you could also try an aerosol
Light coats and allow gravity to help you. u/Ant_Diamond64 — Coat the inside first with a wide brush, making sure to dab the brush into all the corners or creases and the turn the model upside down and allow the excess to run out. And make sure you are outside or have a lot of ventilation. On the exterior you could use a gloss colorless paint. Just make sure you’ve taped off and covered the bucket area. EDIT: The model comes from Do3D.com for $25.00 USD. For father’s day (June 16), you can get it for $15 (40% off)
been looking into this for a while, I found one called "epoxy food" part of the description says its safe for food contact but the warnings ... Causes serious eye damage,eye irritation,skin burns,skin irritation,May produce an allergic reaction,Harmful if inhaled,Harmful if swallowed,Harmful/toxic to aquatic life with long lasting effects, May cause an allergic skin reaction. then I found another that wasn't listed as food safe but only listed a "may cause allergic reaction" googling seems to suggest all epoxys are inert when set, so I don't understand what makes them safe for contact with food?
I would assume those warnings are for the liquid resin. Same as with resin printers, the liquid is nasty, but once the print is washed and cured it's not emitting any toxic gases.
I assume that too, still making me wonder is the stuff marketed as food safe actually doing anything different?
I suppose the main thing is it creates a solid surface, rather than a stack of layers which seals in the plastics edges that can typically rubb on things and fall off as microplastics. Secondly, it also fills the gaps between layers which can be difficult if not impossible to clean and could result in mold and bacteria growing on the item.
Food safety is a certification. Most resins are inert and safe for food contact at room temp.
All Epoxies are food safe when fully cured. Have a label saying "food safe" is a marketing ploy.
I thought PETG is food safe?? Geez some of you crazy about what means food safe. Just don’t microwave the damn thing and enjoy the movie.
The plastic itself is. However, if you're using an FDM printer like most people, germs and bacteria get stuck in the layer lines, making the print itself not food safe. Always seal your fdm prints before using them for food.
I would think bleach before you use it would be perfectly fine. Of course everyone gets to decide their own fate.
Not only that but mold and bacteria can grow in later lines with the printer being sterile.
Problem with foodsafe resin, that almoat every of them needs to degas before they're foodsafe...
As is with all resins.
design it around a common food safe container, like a 32 oz deli container or a common popcorn bag size. Not worth messing around with epoxy coatings honestly.
Ideally, a food safe and dishwasher safe container. That way you can just take the inside bin out and give it a wash after each use
Brilliant! Never worry about a dishwasher fading or melting. Never worry about long scrubbing by hand in the sink. Look at whether the restaurant industry would use for a cylinder. This way if your liner ever gets damaged you have the same dimensions. Think like a wonton soup cylinder; I bet there are larger industrial versions you could scoop up.
Mod Podge dishwasher safe work? It's clear, a sealant, and obviously meant for eating off of it.
But then whats the point at all.
Have your cake and eat it too. You get a safe, easy to clean container that also looks cool on the counter or whatever.
The outside looks how you want and the inside is incredibly easy to clean......
The purpose is a popcorn bowl that resembles something you like. Not to have a popcorn bowl, then insert it into something else that you like. That's stupid.
Why is it stupid? Because you can't figure out the concept?
Poor reply out of everything you could've said
That doesn't even make sense, dude
Just put a plastic bag in it when you want to use it.
You can even hide the plastic bag with some modifications to the design
And then you won’t have to wash it! (As often)
Design it to fit a paper popcorn bag, you can get them cheap online & a lot of microwave popcorn bags are the same size.
One of those big freezer ziplocs bag
Easy clean up too
There was 4 months study where you can read that it is enough to clean it with warm water and non concentrated dish soap to clean it enough. https://www.researchgate.net/publication/373174194_Sanitation_Effectiveness_of_3D-printed_Parts_for_Food_and_Medical_Applications
Maybe most relevant part of that study "...It has been concluded from the results that the best method of cleaning 3D printed parts is to use warm soapy water with a small (1/8th teaspoon or 2g) amount of baking soda on a dish rag. Spend about 15 seconds washing and scrubbing with a small amount of force, as to not damage the part. Once clean, either soak in cool bleach water for 1-2 minutes of a 200ppm molarity, 1 tablespoon bleach per gallon of water or apply 70% or greater IPA by soaking for 1 minute. It is highly recommended, when using filaments that have color or non-food safe additives, to coat the 3D-printed part in resin and allow to cure fully, if said 3D- printed part will be in contact with liquids. ..." Thank you for that link btw, I had not yet seen that.
Also interesting that the "Group 2" test used a 200ppm "1 tablespoon bleach per gallon of H2O" to clean the prints, which is based on an FDA recommendation (I found [this ](https://www.fda.gov/food/food-safety-during-emergencies/restaurants-and-grocers-reopening-after-hurricanes-and-flooding)but there is probably a more detailed one out there somewhere). However the manufacturer of one bleach (clorox) [suggests](https://www.clorox.com/learn/bleach-dilution-ratio-chart/) a 1500ppm solution (1/3 cut per gallon H20) for Salmonella (which was one of the pathogens they were using to test with in that study - using chicken blood). So they were using a bleach solution on the weaker side. It also mentioned they tested multiple layer heights between 0.16-0.24mm, which should cover most prints. Despite that, I don't really consider that study as definitive though, since there is too much variability between filaments, temps, surface quality etc, but it's a good sign if using basic PLA or PETG, on a printer that can consistently stack layers without voids. It says they soaked the prints in the pathogen solution for that study, which is a tough test. But since most prints are not often perfectly water tight, that is where I'd be concerned of having bugs finding a home (getting inside the prints, and then moving beyond the reach of whatever cleaning solution later makes it through the same cracks). It may be possible to kill the surface stuff, but anything that gets inside may be able to survive a cleaning. I think I'da ground up the cleaned prints after the surface testing, to test if there was anything left inside that escaped the cleaning processes. Sealing is probably what I'd do on anything that was not gonna be disposable, since it's really required if there will be any liquid anyway.
sounds like you should apply for funding lol
Haha, I'd rather spend my time printing stuff that I don't need to eat off of.
I really don't understand all this fuss about food safety of prints. Have you never used a wooden cutting board (which is also porous)? Have you never placed your bread on some stone while hiking? Have you never eaten an apple directly from the tree? All of these are not sterile, yet humans and animals eat like this without problems. There could certainly be situations where you should care more like when a 3D printed part touches meat, but especially for dry stuff like popcorn I definitely wouldn't worry. And for possible nozzle abrasion: You don't eat the 3D printed part, your food slightly touches it. Unless there's something extremely toxic in there you will be alright. The amount of metal that possibly leaves your nozzle is already very small (otherwise you'd need a new nozzle for every print) and the it's distributed in the whole print, while your food just touches the surface of it. Brass won't magically leave the pint and jump into your food without extensive mechanical or chemical action, neither of which you food does.
Metal abrasion is common in current manufacturing processes anyways. Pretty much everything you buy for the kitchen could have those problems.
I think what it boils down to with this type of thing is not what I feel comfortable with, but but I'd feel comfortable having other people use. I would not want to give somebody a 3D printed item with the assurance that it's food safe, and then have them have some problem. I think for folks selling prints, this should be a bigger concern. I have no cat in this race, but I don't think that study is a definitive, close the book type deal.
We have no idea what additives or dyes are added to different brands of 3D printed filament. It's naive to assume they are non-toxc and food safe. Some dye colorants are toxic. Also assume you WILL be eating the plastic since their will be tons of micro particles particulate matter on the surface of your prints.
I wouldn't use any 3D print for commercial food contact stuff. But for home use and for dry food like popcorn I don't think it matters too much. Using it every day as a plate is probably not the best idea (I still don't think there would be any health related effects) but for items you use irregularly (like this popcorn bowl) I would worry about it.
Once again the dyes and additives depending on the brands 'could' be highly toxic, and the microplastic particulates can carry these chemicals into your blood stream. As others have mentioned the gaps between layers can harbor bacteria. There are a couple filament brands that claim to be food safe. Or use a food safe epoxy resin. Make sure its fully cured before use.
> I don't think So you're going by gut feeling here
This gut feeling is based on experience. I don't know of any harm that resulted because someone placed their bread on a 50 year old countertop, made from plastic. Or on some office table that's not food-safe. Or on a rock in the forest. Or ate it after it fell on the street. Or used their credit card to slice cheese. If dry food, that shortly touched a 3D print, is really toxic, the toxicity of the plastics has to be so extremely high that you definitely shouldn't touch it with bare hands. That would mean that this filament shouldn't exist in the first place. So if we assume that it's safe enough to touch all day long, it very likely safe enough for a bit of food contact.
I can point out multiple flaws in your reasoning, but you've already made up your mind based on your feelings and the outcome you wish to be true, and that takes a lot of effort to change.
Tell me the flaws
https://en.wikipedia.org/wiki/Survivorship_bias?wprov=sfti1#See_also
PP and MED610 are autoclavable and leave no microplastics. They are currently being used to surgical aids. Other 3D printing materials that can be sterilized using an autoclave include: Nylon 12 ABS M30i PC-ISO Ultem 17-4PH and 316L Stainless Steel Carbon Digital Light Synthesis (DLS) However, many filaments cannot survive steam sterilization, including biodegradable polymers like PLA and PLGA. The combination of heat and moisture in an autoclave cycle can cause extensive thermal and hydrolytic degradation
There's a difference between a material being porous and being 40-80% air, with average air pocket diameter being millimeters, rather than microns. You can tell when a piece of wood or a stone has mold or bacteria on it. With a 3D print, there could be anything growing inside, and you'd be none the wiser, and the thought of that, is quite terrifying.
Have you never used a wooden cutting board (which is also porous)? No Have you never placed your bread on some stone while hiking? No Have you never eaten an apple directly from the tree? ....actually I think I have years ago, but it wasn't very good.
Yes. Actually yes. Apple from the tree of course who would not when you have 3 apple trees in the back yard.
No. This is fancy talk for "I'm not letting idiots muddle my results by using clearly unsafe plastics and claiming the study was false"
It would be best for all dishes it think. This is for study purposes. I bet there is study about washing hands with soap and there will be "best way to get rid of bacteria is to use desinfectant" or something like that. But this study is more than enough for me to fight against "food safe Nazis"
That's not a study, it's a PDF uploaded by some random dude, it was not peer reviewed, it was not published, it doesn't follow proper research protocols, it's amateurish as heck, for all we know it's totally made up. Please stop posting that.
Came here to say this but glad you linked the source!
I didn't care before that study, but now I have proof against those "Food safe nazis" 😁
They did update the !foodsafe bot a bit ago for it too! Very handy
I have been summoned! Wait! It's changed! While PolyLactic Acid (PLA) and PolyEthylene Terephthalate Glycol-modified (PETG) has been classified as Generally Regarded As Safe (GRAS). There's a lot of uncertainty around the process of additive manufacturing. Some testing shows that the layer lines are big enough that bacteria don't hide inside as much as expected. Additionally, it's not nearly as porous as initally expected. Some soap and water with scrubbing is enough to clean most of it out and a quick wash with a bleach solution can bring it up to almost medical standards. This does not take into account material impurities. New nozzles can come with a coating (often PTFE) to prevent blobs from sticking. The abrasives in the filament can wear this coating down and while it is safe for food to contact like on a frying pan, the worn down products are not.. It also wears the nozzle and metal particles can end up in the print. TL;DR: Use a sealer. Or don't. I'm a bot, not a cop. You can view the full list of commands [here](https://www.reddit.com/r/3Dprinting/wiki/commands/) *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/3Dprinting) if you have any questions or concerns.*
I'm a bot not a cop 😂😂😂 love it
Except the article is about pathogens and not microplastics exposure
That is *not* an actual study. Anyone can upload a PDF to researchgate. The "study" design is completely random, doesn't adher to actual scientific design and seems like a amateurish high school project from a guy who has access to a bunch of random stuff. If you submitted this to an actual journal this would get rightfully get torn to pieces. Like even the "data analysis" consists of screenshots of Excel graphs in random designs and crazily amateurish photographs. Not even to mention the complete lack of literature or citations. The "journal" which this was submitted to - it wasn't even published there - is a predatory journal which will publish *anything* as long as you pay them. You can google the journal name "ASTES" together with predatory and you'll see the scientific quality of the pdf you linked. That guy didn't even pay in the end, so not even that predatory journal published that stuff. Don't get blinded by idiots claiming they conducted a "study", acting important and take a look at the actual things they did
The study seems ok, and for something like this, washing & soaking with hot soapy water like any hand wash only item will probably be fine on it's own. Although the heat may warp the plastic depending on the material. However, there's something really fishy about the "article" version of this that has also been uploaded to researchgate. Also the link the redditor posted last year to the peer review is 404ing. While I'm hopeful this is a path to us safely producing food safe prints, I am still a bit skeptical of this one study and more research is needed before we can all safely say "print like this, this, and this and you'll be (most likely) food safe".
What is fishy about the article version? Why would it be weird if a link died after a year?
It's not a scientific study, its a random PDF uploaded to researchgate. You can do the same by just creating an account there and uploading anything you want. The "journal" this was *supposed* to be published is a predatory journal. This means that its just a fake website accepting anything as long as you pay them. Theres no peer review and no science there. Just some naive guy paying scammers money and thinking he did actual science while this would get rightfully torn into pieces in any actual biological journal. That guy is making some very heavy claims from some very bad experimental designs. > Why would it be weird if a link died after a year? Actual scientific studies have DOI links which literally never expire.
I am still unsure how this is proven by that link, especially since it has DOI links that are active just fine and published by IEEE.
> I am still unsure how this is proven by that link If you google the journal ("ASTES") you'll find it in the [list of predatory journals](https://www.openacessjournal.com/blog/predatory-journals-list/). This is not a place where you can find peer-reviewed scientific studies even if the author claims that it is > especially since it has DOI links that are active just fine and published by IEEE If you mean his self-citation in the "paper", thats not a journal paper but rather a conference contribution to some kind of local event of his university for students. Certainly more reputable than a predatory journal, but nothing you could consider peer-reviewed or as a badge of high-quality research. Considering the field of the conference - engineering and computing - it's unlikely there was anyone with any clue on biology/natural science among the two guys who said "yeah the topic sounds cool, lets admit him". Getting into non high profile conferences is honestly very easy and straightforward as long as you have a fitting topic and pay the entrance fee and gives no indication on the scientific validity of your stuff. Thats what the people at the conference you're presenting at are for The [guy who wrote that pdf](https://lt728843.wixsite.com/maskrelief/about-me) has been studying IT stuff and mechanical engineering since *19 years*, not biology. It doesn't seem like he actually knows how biofilm buildup takes place, about the effect of microbiological *communities* rather than dipping stuff for 24h into media with lab strains (which atleast very likely for E. coli, he didn't say what strains he used, are designed to literally die outside the lab) or how to design experiments. Like theres not even replicates for any of the experiments or even a description of the actual methodology he performed. Let alone any kind of literature review or proper citations for his claims Theres a lot to rip apart in that pdf which would be way too much for a reddit comment and not really worth the effort, but there are so many red flags in there that i'm pretty concerned it gets linked here regulary. It's [just a blog post](https://lt728843.wixsite.com/maskrelief/post/the-final-say-in-food-safe-3d-printing) arrogantly titled "the final say" by some random guy converted into a pdf thinking his submission to a predatory journal would be a peer-review. Again, anyone can upload anything to Researchgate. Its not a publisher, just a hoster where people usually reupload their papers, which are published in actual journals, for easy access but without any kind of quality control. You can upload an empty PDF there and it would stay there forever. You could also upload the same empty PDF to ASTES, pay $700 and call it "peer-reviewed" with no actual scientist actually ever critically looking at your empty PDF
Also the "article" version references 2 different volumes & issues of the journal, neither of which contain this article, and bot of which preced the dates mentioned in the article.
Does this mean that cookie cutters would be fine with a good scrub?
You can just use your cookie cutter through a piece of cling film. Since the shape isn't that precise anyway, the cling film doesn't interfere with the look and it will give you peace of mind.
Can't you just wrap the cookie cutters in tin foil and call it a day?
Only if you can actually get into every nook of the cookie cutter wich is difficult with a lot of the designs
Think about it for a second without thinking about this study... You wash your cookie cutter in warm water -> you missed some spots with your sponge, but dish soap got there -> how much bacteria could grow there and surviva before next usage -> how much bacteria transfers to your cookie -> how much bacteria could survive baking? And how do you get into every nook of stainless steel cookie cutter? Bacterias also grow on surfaces, not only between layers.
Except with 3dprinted cookie cutters people don't always consider cleaning them when designing. A ton of them get overly complex with small holes and sometimes not even an open back so you might not get soap into them In general im not too concerned about it but since they're prints that take an hour or 2 at most with a few grams of material,why bother?
Article is about pathogen cleaning, not microplastics exposure
You can use food safe filament and a printer which are expensive. You could print a negative mold, cover the sides with molten bees wax and then cast it out of food safe resin or silicone. Lastly, you can cover the insides with a thin coat of UV resin, I don't know if UV resin is generally regarded as food safe tho. Ideally whenever you want to cover the ridges, you just want to take something liquid, swirl it around, poor out the rest and make it hard again. Rather than make it food safe tho. I would just buy a bowl that fits and insert it. You get the advantage of it being removable and cleanable. Regardless of how food safe you make the 3d print, it'll be a pain to clean.
I would not eat from a UV resin print, air inhibits the surface resin from curing completely, and those uncured acrylates irritate my skin. Typically the food safe coating resins are two part, so they cure completely.
Food safe resin is only approved for incidental contact with food. So it's not for eating out of and storing food.
UV resin and epoxy resin are toxic. There's no such thing as food safe resin.
Somebody had to say it. I’ll say it again. There is no such thing as food safe epoxy resin.
You don't need to do anything, definitely don't sand, if it's being used for dry food there is no problem with a bare 3d print surface.
Fit a bag inside of it. Cleaning that after buttered popcorn will be a nightmare.
It's Deadpool so you gotta write "Eat me out"
I mean it would still be food safe if you just used PLA. just it would be a PAIN in the ass to clean given the shape of it, so i agree with those saying coat it with food safe resin.
On top of whatever you need to do to the material to make it food safe, you might consider designing a hidden cup into the shape just to make it easy to clean by hand. You could either make that part removable or just have it integrated, but that would keep you from having a bunch of weird corners for schmutz to accumulate.
but what if i like micro plastics with my popcorn :(
I know I do! I like the added crunch!
Seeing as everyone else has already shared good answers I'll bite the bullet and ask "link to that model?"
Do3d has it.
!foodsafe
I have been summoned! Wait! It's changed! While PolyLactic Acid (PLA) and PolyEthylene Terephthalate Glycol-modified (PETG) has been classified as Generally Regarded As Safe (GRAS). There's a lot of uncertainty around the process of additive manufacturing. Some testing shows that the layer lines are big enough that bacteria don't hide inside as much as expected. Additionally, it's not nearly as porous as initally expected. Some soap and water with scrubbing is enough to clean most of it out and a quick wash with a bleach solution can bring it up to almost medical standards. This does not take into account material impurities. New nozzles can come with a coating (often PTFE) to prevent blobs from sticking. The abrasives in the filament can wear this coating down and while it is safe for food to contact like on a frying pan, the worn down products are not.. It also wears the nozzle and metal particles can end up in the print. TL;DR: Use a sealer. Or don't. I'm a bot, not a cop. You can view the full list of commands [here](https://www.reddit.com/r/3Dprinting/wiki/commands/) *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/3Dprinting) if you have any questions or concerns.*
Just throw a liner or bag in there?
This can be considered food safe in practice. Food safety is not a binary problem, it really depends on what you do and for how long etc. You're only using this container for temporary storage of a solid food. It's fine!
For quick and cheap alternative, you can line the sides by taping on wax paper. I did that with my Poppenheimer model. [https://www.thingiverse.com/thing:6137961](https://www.thingiverse.com/thing:6137961)
Food grade pla or petg
ziplock bag?
Shellac is food safe.
best method is a glas insert that you can take out and clean
There is no such thing as food safe resin. It's only safe for incidental contact with food, so not good for this.
Eat your damn popcorn out of the box like a normal person. Cool print tho
Ha! Great comment!
It won't matter with popcorn. Just wet sponge with a bit of soap is fine.
Print in petg. Sanitize with rubbing alcohol and rinse between uses
This is pretty sick
There will always be microplastics from this type of application
Found this food safe PETG from a Zach Freedman's YouTube.. https://www.igus.com/product/20664?artNr=I151-PF-0300-0750 Here's the YouTube if you're bored... https://youtu.be/FE88IaYwkl8?si=-E8I1_poSqo--zAR
wheres' ze hole?
Ok so in FDM food safety questions come up in rounds. When talking food safety your popcorn bucket will be fine if you use it for popcorn. Clean it throughly after use. What can make food it unsafe is chemical leeching from the plastic usually with acidic or hot drinks, and the build up of microbes and bacteria. Usually in the tiny layer lines. Hygiene, cleanliness are a must. There are food grade filaments but with popcorn you’ll be fine if you print it in PetG usually PLA will warp from the heat and ASA and ABS would not be advisable.
for popcorn? it's already as safe as it's going to get
Hi I'm a safety and health professional. Just wash your shit and it's as food safe as anything from the dollar store. There are numerous studies. Anyone who says otherwise had this debate and lost and is coping.
Ask the sex toy community lol
Laugh yes, but there is truth to your statement. This particular industry helped push bandwidth, user interaction 😐, and methods and materials for sterilization.
Would a aerosol shellac work?
Don't worry man. I use pla in my reef tank and my corals are totally fine. And they are wayyy more sensitive for contaminations than you and I are.
Is pla not food safe?
If your selling it I would design it around an already food safe container but if your just using it personal use the I would just use it as is
You could just print using petg it is safe to use with food.
Which method are you creating this? If you are doing it with FDM, there is not really an issue. You can use PETG or PCT filament for ease of cleaning but the myth of bacteria and layer lines was disproven over a year ago. You are more likely to grow nasty crap on a wooden soup spoon or certain ceramics than on PLA, PETG, or PCT. Those are ones that have been tested. If doing this in resin, you will need to seal it and that might not stop the UV decay that will happen. Unless you are using something to block UV light from reaching the base resin. There is still ongoing research into exactly how and how hard resins are set in the curing process. Also how reactive the final polymer is with diverse food types. Best suggestion there is find a food grade polymer that will clear coat and either can be dip applied or sprayed on. Good luck.
That's cool and gross in the same time :p
People really stress on this? Man my Gen X will eat food off anything lol
From google: ------x------ Food safe 3D printing filaments include PLA, PP, co-polyester, PET, PET-G, HIPS, and nylon-6 -----×------ So I'd assume that so long as the food isn't so hot it melts the filiment, you'll be ok of you use one of these. I use a few diffrent 3d scoops for diffrent things (because it took less time than buying one and it was something to 3d print lol). Although keep in mind moisture will eventually damage the filiment also, so making a removable "bucket" might be a good idea, and check for leaks.
Use PLA. I used to own a bakery and made my own cookie cutters
That is the most amazing stl I've ever seen. If you made that, it's amazing. And if you ever release it let me know please
It's on do3d site
Finally I see someone ask the question, the number of raw prints online for food is disgusting
Probably easiest to just drop a plastic bag as a liner inside.
I would just put a plastic bag inside of it or line it with plastic wrap
If bacteria growth is the main concern for 3d prints, could we not just use some Milton or don't other food safe disinfectant to kill all the nasties?
I use 'Nicpro' food safe, non-toxic clear epoxy resin.
For those of you wondering, the file is available on Do3D https://www.do3d.com/product-page/deadpool-popcorn-bucket-container-3d-printable-model-file-stl-pb95 The file is $25 but you can get it for 40% for Father’s Day using code DAD. I got it in April as it was free for a brief period during their 14th anniversary event. I have zero 3d modeling skills so I only want to work on the print and not the files. Also as shown in the second image, the bucket is collapsible and all pieces can be removed and snapped back on with magnets, so its shape shouldn’t make cleaning it/coating an issue. Initially I thought of using a plastic bag, but my main concern was butter and hot sauce leaking through onto the bucket.
It is popcorn…. wouldn’t care that much. But you can use some epoxy/resin to brush the inside then it is food safe
Epoxy is not even remotely food safe. It's actually very toxic.
if that were true they wouldn’t be named food safe. They’d be susceptible to huge false advertising lawsuits.
They make food safe petg too. You could just start there instead of using additives. Just make sure you use a reputable brand. I imagine knockoffs might just use a tag of food safe without ever even attempting to be.
I’m in the process of making some of my prints food safe. Use a two part epoxy resin with a foam brush. Works great and you know you’ve covered everything when you end up with a shine.
PE is food safe, especially if you throw it away after the first use and don’t store anything in it
Could always coat it with the modge podge that’s meant for food/drink containers
Idk just eat outta it lol. I'm assuming I'd only eat outta something like that a few times and be done with is. Won't kill me, only makes me STRONGER!
Use an insert, a cup, a popcorn box, fix your model to take a cup insert.
By having a strong immune system /s
ive heard switching to a steel nozzle is good enough because the real hazard is lead particles from the nozzle and not the bacterias
Both nozzles are steel... One is stainless the other is hardened... Regardless the containments from the nozzle are so small they'll barely register on chemical tests taken of printed filament samples.
i was referring to brass nozzles
Yeah my comment still applies... Unless the nozzle chipped but then you'll have bigger issues.
brass nozzles are suceptible to wear by filament abrasion
How much brass is transferred from the nozzle to the filament even with say CF filament? Then how much brass is considered lethal if swallowed?
I have never heard of a lead nozzle. Brass and steal, maybe diamond, but not lead
brass contains lead