this post was submitted on 04 Jun 2026
15 points (100.0% liked)

3DPrinting

22791 readers
418 users here now

3DPrinting is a place where makers of all skill levels and walks of life can learn about and discuss 3D printing and development of 3D printed parts and devices.

The r/functionalprint community is now located at: or !functionalprint@fedia.io

There are CAD communities available at: !cad@lemmy.world or !freecad@lemmy.ml

Rules

If you need an easy way to host pictures, https://catbox.moe/ may be an option. Be ethical about what you post and donate if you are able or use this a lot. It is just an individual hosting content, not a company. The image embedding syntax for Lemmy is ![](URL)

Moderation policy: Light, mostly invisible

founded 3 years ago
MODERATORS
 

I recently printed a vermicomposter in PETG. It consists of a bottom reservoir which is supposed to catch leachate from the above compartments. I'm not sure the rate at which this will fill up, but the leachate is supposed to be diluted with water and used as nutrients from plants.

However, the reservoir leaks from the plug and from the front leg slots, at least when the reservoir is filled completely up with water. The leak from the plug I seem to have fixed with a combination of an o-ring and some PTFE-tape, but for the other leak I've been thinking of coating it with epoxy resin.

My challenge is actually finding such a resin, where the finished, cured product is food safe (since it will eventually find its way into the plants I intend to eat). Locally, I've not been able to find anything that is certified food safe, only various epoxy fillers and primers for boats.

The local 3D-print shop recommended this product which I could get through them: https://siraya.tech/products/siraya-tech-aegis-coating-systerm-for-resin-filament-prints But I've found some less than favorable reviews for that one in particular.

Anyone with experience water-tightening containers like this?

top 21 comments
sorted by: hot top controversial new old

I'd flag this as something to spend money on instead of time on.. Even good manufacturered plastic absorbs odor over time. My guess is the functional life of this will be limited and you will need to reprint it enough times that you're not really being so ecologically friendly anymore. A commercial product might work better and last longer.

[–] DoubleDongle@lemmy.world 1 points 17 hours ago

I've made a couple drinking vessels with food-safe epoxy. Been meaning to try food-safe polyurethane too. And a guy who makes drinking horns has told me that shellac is naturally food-safe too. I don't 100% believe him but I used it on my horn anyway and water tastes okay out of it.

[–] thisbenzingring@lemmy.today 5 points 1 day ago (1 children)
[–] solbear@slrpnk.net 2 points 1 day ago (1 children)

Oh, that is an interesting idea that I hadn't thought of. I might be able to buy it from a local beeskeeper, and I think I have a small amount lying around somewhere I could test with.

[–] thisbenzingring@lemmy.today 1 points 22 hours ago* (last edited 22 hours ago)

Warm it up enough to roll it into sheet and heat gun it into place. Food safe and waterproof plus should hold up for a long time

[–] radau@lemmy.dbzer0.com 1 points 21 hours ago

Max CLR has a two part food safe epoxy resin that's good for prints and other things

[–] noride@lemmy.zip 3 points 1 day ago (1 children)

Which slicer do you use? There is a setting a that can improve water retention capabilities with just a check box. I think it's called "stagger perimeters" in Bambu for example. Also use at least 3 walls. Some good tests and examples on YouTube by "Designed to make" if you're curious.

[–] solbear@slrpnk.net 2 points 1 day ago (1 children)

I am using PrusaSlicer. Not sure if that check box is present in that, or if it was added in OrcaSlicer or BambuSlicer.

I might've printed with only two walls, I will need to check tomorrow when I'm at the correct machine. And thanks for the video recommendation, I will be sure to check it out!

[–] SaveTheTuaHawk@lemmy.ca 2 points 1 day ago* (last edited 1 day ago) (1 children)

Three walls of PETG should be water tight. if not, you are under extruding.

[–] solbear@slrpnk.net 1 points 1 day ago

I might've printed with only two. But I'd like to avoid having to reprint, if possible, and instead fix it with some post-processing. I think the leakage is actually concentrated on certain points near the front leg slot, so it does not seem to generally seep through the entire bed.

[–] grue@lemmy.world 1 points 1 day ago

Locally, I’ve not been able to find anything that is certified food safe, only various epoxy fillers and primers for boats.

Call the manufacturer of the locally-available epoxies and ask them what they recommend.

I went looking for contact info for one common brand as an example, but found instead this product support article that suggests, to me at least, that their "limited food contact"-rated epoxies would be good enough for your use-case.

(I never did find a phone number or email for product support, but they do at least have a chat widget, so... 🤷)

[–] Anarki_@lemmy.blahaj.zone 1 points 1 day ago (1 children)
[–] solbear@slrpnk.net 2 points 1 day ago (1 children)

Didn't think of aquariums. Would assume this should be food safe, since it will be in contact with environment of living things. Would you happen to know whether it has any good adhesion to PETG?

[–] Anarki_@lemmy.blahaj.zone 1 points 1 day ago (1 children)

Unfortunately I do not. I should have checked before posting, sorry.

[–] solbear@slrpnk.net 2 points 1 day ago

Oh no, don't worry - it was a great suggestion, and I'll check it out for myself, just asked in case you already knew :) Thanks!

[–] Lasherz12@lemmy.world 1 points 1 day ago (2 children)

I personally would not consider superglue harmful enough to worry about plants seeping enough of it to affect the health of me eating the plant, and it's not food grade. I've used it to fix cracked humidifier reservoirs in a greenhouse for example. That being said, most epoxy resin dries food grade. I don't think you'd have to search hard for a very well performing Resin with food grade search term swapped with dining surface or some frequent use that requires food grade.

[–] scutiger@lemmy.world 2 points 1 day ago (1 children)

Superglue is used in all kinds of stuff that we come into contact with every day. Dentists and orthodontists even use it inside our mouths.

[–] solbear@slrpnk.net 2 points 1 day ago (1 children)

I would have assumed that dentists do not use the same consumer-grade stuff you buy in your local shop. Do you know for sure that they do?

[–] scutiger@lemmy.world 2 points 1 day ago

I dont know if its the exact same as consumer grade glue, but it`s definitely CA glue.

[–] solbear@slrpnk.net 1 points 1 day ago

I personally would not consider superglue harmful enough to worry about plants seeping enough of it to affect the health of me eating the plant, and it’s not food grade. I’ve used it to fix cracked humidifier reservoirs in a greenhouse for example.

I would want to avoid something that leeches off into the water. That said, I am going to dilute it quite a lot since the stuff will be very concentrated. Super glue could be a little expensive for this though? I think coating the whole bed would take multiple small containers.

That being said, most epoxy resin dries food grade. I don’t think you’d have to search hard for a very well performing Resin with food grade search term swapped with dining surface or some frequent use that requires food grade.

I know very little about epoxy resin, but that is what I often see - but is it really basically the same stuff that is used to repair boats as people use for decorations? The safety data sheets for the components are always pretty rough, but they of course say nothing about the cured state.