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I broke a coffee mug over the weekend, it was new, I wanna fix it.

Looks like stake of the art is Epoxy and most epoxy isn't food safe?

Art Resin brand Resin is FDA certified food safe (they say FDA certified and in Canada and Great Britain and 13 other countries, which is a claim you can't make without getting in very fraud, but also worthless), but it only allows up to 50°C before that's worthless.

The MSDS on other resins and epoxies seems to be not food-safe?

Anyone know how to fix a coffee cup?

Was thinking maybe finding some non-PB tin?

#ceramics
#repairability #repair

in reply to silverwizard

Fun fact - there are a billion articles on how to do this - all made by an LLM who doesn't know what food safe is and is just recommending random glues
in reply to silverwizard

Wild, I would have just grabbed some super glue, but Gorilla glue says specifically don't use where it might come in contact with food, now that I check...
in reply to Resuna

@Resuna The problem is that for those kits I'd want to see their heat data and food safety data, since a lot of the examples are cold examples.
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@Granny Art (Shrimp)vis.soc mod @Surly Amy Gotta use the right epoxy - needs to be similarly strong. I am repairing the side, not the handle, which holds weight.
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@Steven Hoefer Yeah, raw melted tin with a silicone heat resistant brush and melted tin is *probably* enough - but uh - yeah - not super duper safe.
in reply to silverwizard

@artcollisions @SurlyAmy I was about to jokingly suggest that you could drill, tap and use screws/bolts, but then my Google search resulted in ceramic bolts and now I want one. Or a bag of them. They look too nice but even more fragile.

If I had to repair a mug I'd either use the 50 °C resistant epoxy and hand wash it afterwards or (if it'd be the handle) use any temperature resistant glue anyways.

(Photo source: ortechceramics.com/products/ce… )

in reply to Gabor Heja

@Gabor Heja @Granny Art (Shrimp)vis.soc mod @Surly Amy The probably is less the washing and more the making coffee directly in it with 100°C water.

Those bolts look really cool - I wonder what primary use for them is.

in reply to silverwizard

@rasterweb Here’s a rabbit hole directly related to repairing broken pottery:

youtu.be/MIoi-DSm0e4

This entry was edited (1 year ago)
in reply to silverwizard

Oh... I did not consider that... maybe I should also make a coffee.
in reply to silverwizard

Cyanoacrylate? It's hard to wade through the AI generated link spam on Google for info on food safety (this one claims Krazy Glue is, Krazy Glue's site is less positive tbbonding.com/is-tech-bond-foo… ), but I know there are wound contact formulations...
in reply to Dan Lyke

@Dan Lyke Yeah - that says safe if not in direct contact with food - which I don't think works since it's a large broken chip. But yeah! This is it! An hour of LLM spam to find something and then read data and not quite right.

The wikipedia page definitely supports the reading that it's probably not good for eating off of.

Also! Thanks so much for digging for me!

in reply to silverwizard

Yeah, for personal use I'm cavalier enough that wound safe sounds good enough to me, the standards for food safe are amazingly high, but I'm also getting to the "at some point the long term risk factors become less concerning" age...

Are the platinum cure silicones clear? Because that might work for a chip.

in reply to Dan Lyke

@Dan Lyke Damnit - I'm an idiot - just checked the silicon *literally sitting on my desk right now*

It's safe to eat out of and heats to 400 degrees F

in reply to silverwizard

@silverwizard This was a cheeky guess. A more general guess would be strong electromagnetic field applications where metal screws could interfere with the fields.
in reply to silverwizard

Epoxy is food safe when cured. Mix it completely and give it a day to cure.

Superglue (cyanoacrylate) also works fantastically on ceramic even though it was developed for medicine.

in reply to Joshua A.C. Newman

@Joshua A.C. Newman :condemned: What do you mean food safe when cured? Is there a test for this? I am a little bit cautious about this kind of thing - it seems to be the case for Art Resin but not all resins? But the problem there is debonding at high temp?
in reply to silverwizard

Yeah, I see that. So, if Art Resin is certified, why wouldn’t you use that? (Or cyanoacrylate, which is cheaper, very fast-curing, very strong, and originally for medical purposes?)
in reply to silverwizard

Cured epoxy is nonreactive. It’s used to make artificial body parts. If you’re worried about leftover, uncurred resin or hardener, they both dissolve in acetone so you could wash it afterward.

However, if the fit is still good, superglue will be easier. And that stuff cures quick and completely!

in reply to silverwizard

@artcollisions TBH, I don’t know of any truly safe way to repair ceramic mugs that makes them useful again. Only ways that makes them decorative.
in reply to silverwizard

@gheja @artcollisions ceramics are often used on the surface of spacecraft and other high temp objects because they can withstand higher temperatures than metals that melt so I’m going to assume it’s for that instead of firearms and pretend society isn’t garbage. Hahaha
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Surly Amy
@semiotic_pirate @artcollisions you can’t use the gold to eat out of tho. It’s not food safe. Just decorative. And not strong enough to hold a handle.
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Surly Amy
@semiotic_pirate @artcollisions that’s a good question. I’ll ask my dentist in two weeks!