7 ms·

Repairing my mug with Kintsugi

641 points by fellerts 2y ago

throwup238 2y ago
> These days, some hobbyists opt for modern epoxy instead of the traditional and expensive Urushi lacquer. Epoxy probably yields a more robust bond and certainly allows for quicker repairs, but I question its safety for food-related use, especially at the temperatures found in a steaming cup of coffee. People opt for epoxy because Urushi lacquer is traditionally made from poison oak sap and is a potent skin irritant to most people (it's where urushiol gets its name). It's really tough to do Kintsugi without smearing trace amounts of it all over the place, especially if you're doing it with kids, and cleaning it off is a pain since it's a hydrophobic sap. Even trace amounts can cause a reaction, especially if someone has sensitive skin or is severely allergic. People who do a lot of kintsugi develop a tolerance for it but it's an annoyance that most hobbyists just don't need. Epoxies can be perfectly food safe and the FDA has a database [1] although it's not particularly user friendly. You can get MAX CLR or similar from Amazon. I wouldn't use it in an oven above 300F but it's fine for boiling temps. These FDA approved two part epoxies are used all over the place in hospitals and food manufacturing facilities where they're used to coat rough surfaces that would otherwise harbor bacteria. [1] https://www.cfsanappsexternal.fda.gov/scripts/fdcc/?set=IndirectAdditives&sort=Sortterm_ID&order=ASC&startrow=1&type=basic&search=epoxy https://www.cfsanappsexternal.fda.gov/scripts/fdcc/?set=Indi...
- giraffe_lady 2y ago
  I spent a few years messing with different approaches with epoxy but I never found anything that could replace urushi. It's really hard to get foodsafe epoxy to cure as hard as urushi, though I did eventually get one I was happy with. But the wheat flour in the traditional material pulls the shards together as it dries, and gives just an incredibly tight and strong bond that can really hold up to actual use of the restored vessel. Epoxy always weakens and fails after a while, while I have urushi/wheat/clay pieces that have been in daily use for years. Depending on your goals though non-foodsafe epoxy can work well. Thickened marine epoxy, for under-the-waterline boat repairs is rock solid for decorative items. I'm sure it's toxic af and I wouldn't want it anywhere near my food but it would be fine for a lot of the things people want to do kintsugi for. Cashew lacquer is also pretty cool. It's nowhere near as nasty as urushi and doesn't require a special environment for curing. If I were just getting into it now I'd probably start with that.
  - pvaldes 2y ago
    > Cashew lacquer Hum... That can't be a coincidence. Both plants are on the same family. Let me check... Yup, Cashew produces urushiol also. Unlike pistachos, cashew shells must be removed before selling the fruits for this reason. So cashew plants can trigger skin allergies. Is a common family thing. Harvesting this things burn the workers hands. My bet is that would be also unsafe for people allergic to poison ivy.
- elihu 2y ago
  Weirdly enough, the food safety of urushiol was the topic of this recent and heavily discussed HN post: https://news.ycombinator.com/item?id=40399224 https://news.ycombinator.com/item?id=40399224 I can't say I have any desire to try it myself.
  - fellerts 2y ago
    I'm not a doctor/chemist, but as far as I understand, the polymerization of urushiol renders it hard and inert. Your thread discusses contact with raw urushiol as found in poison ivy, cashew sap (and apparently mangos) which is indeed known to cause allergic rashes in most humans. I'm not saying that kintsugi is definitely food-safe, but it's an important distinction. Side-note: I did get some raw urushi on my fingers while working on this project, but nothing happened. Perhaps I'm immune.
    - throwup238 2y ago
      > Side-note: I did get some raw urushi on my fingers while working on this project, but nothing happened. Perhaps I'm immune. Might also be enough mechanical rubbing on fingertips during normal use that it mostly scrubs off. Whenever I feel it coming on from Urushi or accidentally touching poison ivy in nature, I rub it with water and course sand/dirt which seems to get rid of the urushiol.
      - qwerpy 2y ago
        How do you “feel it coming on”? Would love to develop a sense for it so I can save myself from days of discomfort.
        throwup238 2y ago
        I have sensitive skin so I start to itch shortly after contact and it builds from there. If I get it scrubbed off fast enough after exposure, I can usually prevent full contact dermatitis from setting in. Urushi is more of a pain in the ass because its made from the sap, but Windsor and Newton artguard barrier cream seems to really help. Ideally apply it before use but it helps washing it off too if you forget.
- Schattenbaer 2y ago
  You can even get (tobacco) smoking pipes decorated using urushi. It's made me wonder about the temperature stability, as a pipe can (but ideally shouldn't) get fairly hot. Tsuge is a good brand to search for if you want to see exanples. Cost-wise such pipes start around the two hundred US mark.
- harimau777 2y ago
  I've never trusted that food safe epoxy actually is. I'm afraid that lobbyists have interfered, or its a situation where "there's no evidence that it's dangerous but there's not really evidence that it's safe", or the studies are funded by manufacturers, or there's something like manufactures pulled with BPA where they just switch to something functionally equivalent to a potentially dangerous chemical. Is there any reason to believe that these epoxies won't just be like PFAS where in a few years the EPA/FDA will decide that they were actually risky?
  - doctorhandshake 2y ago
    I’m with you. I assume all plastics to be unsafe for human use by default.
  - mortify 2y ago
    It's confusing. There's food grade and food safe. There's some more information here, and it's still confusing. https://www.wisebond.com/blogs/epoxy-blog/is-epoxy-food-safe https://www.wisebond.com/blogs/epoxy-blog/is-epoxy-food-safe
- bee_rider 2y ago
  I’m always worried about food-safety and Amazon. They don’t have very good control over their inventory, right?
thot_experiment 2y ago
I recently broke a piece of glassware that had been with me for over a decade. I have all the pieces and I'm wondering if it's possible to stick it in a kiln and run a heat cycle that will cause all the cracks to flow together without deforming the shape, and barring that if there's a thin gold glue I could use to do some approximation of this technique but with cracks that are essentially zero width.
- throwup238 2y ago
  A very skilled glassmaker might be able to fuse the pieces together by heating the edges and pushing them together if the piece is simple enough but in general, no. That's why it's called glass blowing: the air pressure is what gives the glass form while it cools and vitrifies.
- chris1993 2y ago
  The BBC “repair shop” show recently (last year?) had an episode repairing a shattered vase with some specialist glass repair glue, so you can probably find some for this.
- hcrean 2y ago
  There is a method where you piece the glass together supported in investment, (a type of ceramic casting plaster), by building it up in layers. You tightly pack it and put it in the kiln, the investment holds the shape of the object when it melts. This is a very advanced and difficult method of glass re-forming.
- Baeocystin 2y ago
  The short answer is no. You will not get fusion without slump. That being said, there are excellent, optically-clear, UV stable epoxies that are made for this problem. Hxtal is the go-to for most. https://www.lakesidepottery.com/HTML%20Text/Tips/Hxtal-NYL-instructions-glass-epoxy.htm https://www.lakesidepottery.com/HTML%20Text/Tips/Hxtal-NYL-i... It is very thin, and will happily wick in and fill cracks. Often the join is completely invisible. The downside is that the cure time is on the order of 1-2 weeks. It does take a little practice to use effectively, and it's worth trying on less-important projects first, but it's straightforward enough that you can expect success if you follow the directions carefully.
thingsilearned 2y ago
For those of you in the Bay Area there’s a great Kintsugi workshop that’s run out of the SF zen center almost weekly https://stonegoldcrafts.com/ https://stonegoldcrafts.com/ I got into Kintsugi when my toilet needed repair. It’s a rewarding craft https://thingsilearned.com/things/my-kintsugi-toilet/ https://thingsilearned.com/things/my-kintsugi-toilet/
- avtar 2y ago
  For those in Toronto :) https://introjapan.ca/inperson-classes/ https://introjapan.ca/inperson-classes/ No affiliation. I gifted my partner an intro workshop pass and she's been returning for more classes since then.
  - criddell 2y ago
    How do you discover classes like this? Are there city-specific guides to interesting classes and seminars that you can take?
    - mholt 2y ago
      I'm also looking. The University of Utah has a random one-off kintsugi course this fall but I think it's full already.
    - avtar 2y ago
      I wish I could offer something more useful, but in this case her birthday was fast approaching and I remembered her bringing up Kintsugi in a conversation. I did a search for "kintsugi toronto" and found that teacher's site on the first results page. Back in the day I would have browsed craigslist, but unfortunately it's not as popular here anymore.
- kelnos 2y ago
  I've attended one of those at the Zen Center! My partner took me to one as a birthday present last year. She ended up being kinda frustrated with the process, but I found it soothing and relaxing, and left happy and contented. The guy running the workshop had us use epoxy and not urushi powder (not surprising; I'm sure all of us would have ended up with severe skin irritation otherwise). The article mentions concerns about food safety; IIRC we were told that the epoxy we were using in the workshop was not food safe, but that it's easy to acquire food-safe versions of it. We also didn't do this in anywhere near as many steps, with as many different treatments for different sizes/shapes of damage. Ultimately we fully repaired a piece in a couple hours, not the several months that the article author took to do it right. (And the extra care and use of the proper materials shows; the final repaired alligator mug from the article looks orders of magnitude better than my work.)
JSR_FDED 2y ago
This is super inspiring and the end result is amazing, congratulations!
kelnos 2y ago
> I knocked it off the kitchen counter and, giving into the idiotic reflex of trying to catch it with my foot, kicked it into the wall instead Not idiotic! I've saved more things than I've further damaged by doing this.
- sunaookami 2y ago
  Unless you are dropping a knife ;)
  - mauvehaus 2y ago
    Or the business end of a blender. Or a big-ass chisel. Not hypotheticals, either of those, and not me.
    - smeej 2y ago
      I have a chisel scar on my hand that I call my "get down and move the damn ladder" reminder scar.
  - jen729w 2y ago
    I’ve done this with a new and thus terribly sharp knife. I’d bought it for my mate, so when I knocked it off the bench my reaction was oh no! damage! catch! The kitchen looked like a scene from Kill Bill. Perfect blood spray in an arc across the wall. This mate lived with me at the time. And he was a nurse. He came home from his shift about half an hour later and I told him, sorry man, but you’re driving me straight back to the hospital. I’m lucky to still have total use of my right middle finger.
  - namibj 2y ago
    That's why you keep a second mode trained that instead makes you jump away from the uncontrolled blade.
  - smrq 2y ago
    Once, many years ago, I dropped a knife and caught it, fortunately by the handle. I felt very stupid for the obvious reason, but my cat was by my feet at the time--so I'm not even sure it was the wrong thing to do. Well, crisis averted, one way or another...
giraffe_lady 2y ago
This is really great results for an early project, none of my first few came out anywhere near so good. I've been doing traditional kintsugi for about twelve years, a couple hundred successful repairs. Though when I started there was very little instruction or english-language resources available. It's become pretty popular for obvious reasons which is great for people getting into it now. It remains probably the most difficult and frustrating skill I've ever learned. It's really hard to communicate just how meticulous, near-impossible some of the joins can be. There is a huge variety of technique and nuance to learn about different media and lacquer ratios for different kinds of joins & fills and it all needs to be done by intuition and experience. And then the medium has no holding power until the curing process is well underway. So you need a lot of creativity to come up with a scaffolding system, pretty much completely unique to each project. Any problem after applying lacquer means hours of careful filing and rework, and more days or weeks of curing. An edge-of-my-skill repair on a complete shatter takes about 100 hours spread out over 2-3 months. Even just an ideal three piece clean break is easily 8-10 hours and a handful of weeks.
- fellerts 2y ago
  Thank you for the kind words! I've not even scratched the surface of kintsugi of course, but the little I've learned agrees very much with what you say. It's a true test of patience. Are you entirely self-taught then, or did you find a mentor?
  - giraffe_lady 2y ago
    Almost entirely self taught. I've got a few other practitioners I've asked for advice over the years but no one who really had guidance over my learning the way a mentor would. Early on I got most of my info from the newberry library. It had a collection of illustrations and manuals donated from a defunct lacquerworks museum in japan, for some reason. They had someone around who even helped with a lot of translation for free which was a major help. All this stuff is available and better explained on youtube now though.
- cafebee 2y ago
  I’m working on a shattered teapot and am finding the scaffolding part very difficult. Any tips on holding pieces in place that you’d be willing to share?
talkingtab 2y ago
Danger!!! Urushi is basically poison oak/poison ivy sap. Not quite the same, but in that family and with the same effects. Not to scare you off, but if you are interested in this, imagine all the things that can go wrong from if you were to get a tube of poison ivy sap and then do things with it. That said, Urushi is great and the number of things you can do with it is truly amazing. Just don't do it rashly.
- smoyer 2y ago
  > rashly Good one!
- userbinator 2y ago
  Most other adhesives and epoxies are also quite toxic when not cured.
  - LoganDark 2y ago
    Even if you're not allergic the first time you use them, you can become allergic.
- b112 2y ago
  Sir...sir! This is hacker news! It's not some place to say somthong punny! What are you, The Punisher?
serf 2y ago
aside from 'the craft' and tradition of the process, is there any real benefit to using legitimate urushiol? there are lots of bonding agents and epoxies out there that are not urushi based , actually food safe, and just as easily doused in gold dust, and completely compatible with prepared ceramics.
- mholt 2y ago
  What's food-unsafe about cured urushi?
  - conkeisterdoor 2y ago
    I don't think the GP was implying that urushi isn't food safe, but rather that some epoxies aren't food safe
    - MBCook 2y ago
      The author of the peace also mentioned that while there are food safe epoxies they were worried that they may be less food safe than expected when used with high temperatures like tea or coffee as opposed to being used in a simple serving dish.
      - xipho 2y ago
        According to https://www.lakesidepottery.com/Pages/Pottery-tips/ceramic-repair-and-restoration-questions-and-answers.htm#Anchor-Questio-57445 https://www.lakesidepottery.com/Pages/Pottery-tips/ceramic-r... there are no food safe epoxies, including Kintsugi...
        ryandamm 2y ago
        Certified food grade epoxies are used in industry all the time; in fact, some wine is aged in epoxy-coated concrete tanks, and the inside of soda cans these days includes a thin layer of food-grade epoxy. I will not fault anyone for not believing the certification, but I would personally want to see a more authoritative source than an undated ceramics FAQ. But this is just personal style! Being suspicious of regulatory thresholds is prudent. (And this FAQ has me wanting to revisit my priors and research this a little more specifically, because its assertions are plausible, but need sources or explanations or dates, for cross-checking. Food-grade epoxy I believe in would be a handy thing to have exist; I do have some certified food grade epoxy in my garage that I haven’t used for anything yet and I’d dislike downgrading it to just “epoxy.”)
mholt 2y ago
My wife recently got into kintsugi. She's learning the traditional method described here. I'm reading these comments with great interest and will be passing this onto her! Most of the methods taught in the US are "gold relief" methods, which is basically glue with golden pigment mixed in. It doesn't look great but is modern and quick. "Gold flush" methods take a bit more time and are more authentic, but still don't use the traditional materials shown in this article. Does anyone know where to get these traditional materials for use in classroom settings (i.e. in bulk, preferably discounted)? Not massive scale, just enough for a few classes. The kits have such a tiny amount and are so expensive, even a bulk discount of ~10-20% would be ideal.
yegle 2y ago
Apparently there's another styles of repairing ceramic/porcelain: https://zh.wikipedia.org/zh-hans/%E9%94%94%E7%93%B7 https://zh.wikipedia.org/zh-hans/%E9%94%94%E7%93%B7
- modernpink 2y ago
  Apparently, it was this Chinese method of repair that horrified the Japanese aesthetic sensibility [0] into creating kintsugi. [0] https://en.wikipedia.org/wiki/Kintsugi#Origin https://en.wikipedia.org/wiki/Kintsugi#Origin
vsgherzi 2y ago
wow it's beautiful. Amazing job. Can you still use it in a dishwasher or microwave?
- giraffe_lady 2y ago
  I have a bunch of kintsugi stuff in regular use so I can answer. Microwave is a definite no! It arcs, kind of like gold-rimmed plates would I guess. Dishwasher you can. The repair is really two parts: the bond that holds it together and the gold dust that covers the lacquer. The join bond can handle the dishwasher. The gold layer needs touchup every few years anyway, but it will need it a lot more often if it goes through the dishwasher regularly. Gold is expensive. There are some other ways of applying the gold that can hold up better, but they're less common.
dlbucci 2y ago
This is awesome! The handle on my favorite mug broke off recently. I tried super gluing it back on, but it broke off after a few trips through the dishwasher (hand washing got old). I was gonna try epoxy next, but I try to avoid that stank whenever I can. Maybe I'll give this a shot.
- pjerem 2y ago
  Repairing the handle can be dangerous. It means that your repair is going to support the entire weight of your mug + the (hot) liquid.
tern 2y ago
I tried to order a kit with urushi powder from Japan recently and they had to cancel the order, saying it was now illegal to import into the US
astrea 2y ago
I had no idea it was done with a resin.
dudeinjapan 2y ago
I repaired mine with glue
piyh 2y ago
I repaired my mug with epoxy and kept using it for years until the handle fractured at the same spot, dropped on my trackpad and shattered it. Now I get new mugs when one breaks.
AdamN 2y ago
Is there a place that can do this for me?
- notdang 2y ago
  If you are in US: https://www.lakesidepottery.com/Pages/ceramic-repair-and-restoration-request-form.html https://www.lakesidepottery.com/Pages/ceramic-repair-and-res...
silcoon 2y ago
Look better than new in my opinion
roywashere 2y ago
When I was a kid I had a mug with my name on it that was gifted to me. My mother broke the ear off at some point and decided to glue it back on. A week later she handed me a steaming hot cup of tea and the ear tore off and I got severe burns on my leg as a result. Not great. As a result I am a bit wary fixing stuff meant to contain hot liquids
- pmarreck 2y ago
  I think anyone would after that experience! Yikes!
infecto 2y ago
Is it a good idea to use these as drinking vessels after repair? I always assumed the risk was too great. Even if you use some sort of epoxy over it, I would be concerned with contamination from the cracks not being fully sealed.
1970-01-01 2y ago
This is once again a perfect use case for cyanoacrylate. There's FDA approved, food-safe brands that will simply allow you to rebuild every fragment into the cup. It will also cure into ceramic in under a minute. I say this because I've done it. You're wasting time and energy using any other method.
- akpa1 2y ago
  I suppose it comes down to if you're purely in it for utility or if you're trying to repair this thing of yours precisely because it's this thing of yours. I'd be far more inclined to go to the lengths discussed in the article for a precious mug that I've used for a decade than I would for a mug I'd had for two, even if I'd still want to repair both out of thriftiness. It's a labour of love.
- JoBrad 2y ago
  Honestly, using CA is what I and many other folks would use, in this situation. I’m a huge fan of J-B Weld’s Superweld light-activated glue. In the right lighting, you can see the steam puff from the glue when you activate it. But OP’s process brings to mind the way we remember things: by reliving them in such a way that can (and usually does) produce a unique and slightly different product from the original. It’s the investment of time, thought, and love that makes this process more desirable. I’m reminded of a recent comment thread on Jaloponik, where some great heads were talking about just _why_ the fact that anyone can go 0-60 in less than 4 seconds isn’t actually a great as it seemed to be. I’m a nutshell it came down to the fact that this used to be the product of untold hours spent learning and iterating to eke out tenths of a second, over time, to finally reach that level. Admittedly it smacks of gatekeeping, but there is a fine line between gatekeeping and rewarding true mastery of an art.
- bee_rider 2y ago
  Does it look nice? The aesthetic is part of the whole thing, I think.
AJRF 2y ago
I think i'll try do this next time I smash a mug (maybe avoiding the Urushi lacquer as others have mentioned in this thread). It gives the mug so much character, looks better than before, and for sure it will be a conversation starter!
oofabz 2y ago
This mug is well on its way to becoming a tsukumogami.
bqmjjx0kac 2y ago
Did anyone else notice they pixelated their fingerprint in the "goldfinger" photo? 10/10 points for opsec.
- fellerts 2y ago
  I was waiting for someone to notice that. Good eye!
asshatdev 2y ago
[flagged]
- coolspot 2y ago
  It is too obvious what you’re trying to do.
hoseja 2y ago
I was somewhat disappointed when I learned this is not, in fact, done with a gold-based solder.
Talkative32 2y ago
[flagged]
phillias 2y ago
ITS POISON IVY! Do not breath in that stuff! I ended up the hospital with my face all bloated. No kidding. Japanese harvest from the urushi tree containing urison the irritant in poison ivy! I think they get off on shipping this stuff to American's laughing at them.

641 points by fellerts 2y ago

> These days, some hobbyists opt for modern epoxy instead of the traditional and expensive Urushi lacquer. Epoxy probably yields a more robust bond and certainly allows for quicker repairs, but I question its safety for food-related use, especially at the temperatures found in a steaming cup of coffee. People opt for epoxy because Urushi lacquer is traditionally made from poison oak sap and is a potent skin irritant to most people (it's where urushiol gets its name). It's really tough to do Kintsugi without smearing trace amounts of it all over the place, especially if you're doing it with kids, and cleaning it off is a pain since it's a hydrophobic sap. Even trace amounts can cause a reaction, especially if someone has sensitive skin or is severely allergic. People who do a lot of kintsugi develop a tolerance for it but it's an annoyance that most hobbyists just don't need. Epoxies can be perfectly food safe and the FDA has a database [1] although it's not particularly user friendly. You can get MAX CLR or similar from Amazon. I wouldn't use it in an oven above 300F but it's fine for boiling temps. These FDA approved two part epoxies are used all over the place in hospitals and food manufacturing facilities where they're used to coat rough surfaces that would otherwise harbor bacteria. [1] https://www.cfsanappsexternal.fda.gov/scripts/fdcc/?set=IndirectAdditives&sort=Sortterm_ID&order=ASC&startrow=1&type=basic&search=epoxy https://www.cfsanappsexternal.fda.gov/scripts/fdcc/?set=Indi...

giraffe_lady 2y ago
I spent a few years messing with different approaches with epoxy but I never found anything that could replace urushi. It's really hard to get foodsafe epoxy to cure as hard as urushi, though I did eventually get one I was happy with. But the wheat flour in the traditional material pulls the shards together as it dries, and gives just an incredibly tight and strong bond that can really hold up to actual use of the restored vessel. Epoxy always weakens and fails after a while, while I have urushi/wheat/clay pieces that have been in daily use for years. Depending on your goals though non-foodsafe epoxy can work well. Thickened marine epoxy, for under-the-waterline boat repairs is rock solid for decorative items. I'm sure it's toxic af and I wouldn't want it anywhere near my food but it would be fine for a lot of the things people want to do kintsugi for. Cashew lacquer is also pretty cool. It's nowhere near as nasty as urushi and doesn't require a special environment for curing. If I were just getting into it now I'd probably start with that.
- pvaldes 2y ago
  > Cashew lacquer Hum... That can't be a coincidence. Both plants are on the same family. Let me check... Yup, Cashew produces urushiol also. Unlike pistachos, cashew shells must be removed before selling the fruits for this reason. So cashew plants can trigger skin allergies. Is a common family thing. Harvesting this things burn the workers hands. My bet is that would be also unsafe for people allergic to poison ivy.
elihu 2y ago
Weirdly enough, the food safety of urushiol was the topic of this recent and heavily discussed HN post: https://news.ycombinator.com/item?id=40399224 https://news.ycombinator.com/item?id=40399224 I can't say I have any desire to try it myself.
- fellerts 2y ago
  I'm not a doctor/chemist, but as far as I understand, the polymerization of urushiol renders it hard and inert. Your thread discusses contact with raw urushiol as found in poison ivy, cashew sap (and apparently mangos) which is indeed known to cause allergic rashes in most humans. I'm not saying that kintsugi is definitely food-safe, but it's an important distinction. Side-note: I did get some raw urushi on my fingers while working on this project, but nothing happened. Perhaps I'm immune.
  - throwup238 2y ago
    > Side-note: I did get some raw urushi on my fingers while working on this project, but nothing happened. Perhaps I'm immune. Might also be enough mechanical rubbing on fingertips during normal use that it mostly scrubs off. Whenever I feel it coming on from Urushi or accidentally touching poison ivy in nature, I rub it with water and course sand/dirt which seems to get rid of the urushiol.
    - qwerpy 2y ago
      How do you “feel it coming on”? Would love to develop a sense for it so I can save myself from days of discomfort.
      - throwup238 2y ago
        I have sensitive skin so I start to itch shortly after contact and it builds from there. If I get it scrubbed off fast enough after exposure, I can usually prevent full contact dermatitis from setting in. Urushi is more of a pain in the ass because its made from the sap, but Windsor and Newton artguard barrier cream seems to really help. Ideally apply it before use but it helps washing it off too if you forget.
Schattenbaer 2y ago
You can even get (tobacco) smoking pipes decorated using urushi. It's made me wonder about the temperature stability, as a pipe can (but ideally shouldn't) get fairly hot. Tsuge is a good brand to search for if you want to see exanples. Cost-wise such pipes start around the two hundred US mark.
harimau777 2y ago
I've never trusted that food safe epoxy actually is. I'm afraid that lobbyists have interfered, or its a situation where "there's no evidence that it's dangerous but there's not really evidence that it's safe", or the studies are funded by manufacturers, or there's something like manufactures pulled with BPA where they just switch to something functionally equivalent to a potentially dangerous chemical. Is there any reason to believe that these epoxies won't just be like PFAS where in a few years the EPA/FDA will decide that they were actually risky?
- doctorhandshake 2y ago
  I’m with you. I assume all plastics to be unsafe for human use by default.
- mortify 2y ago
  It's confusing. There's food grade and food safe. There's some more information here, and it's still confusing. https://www.wisebond.com/blogs/epoxy-blog/is-epoxy-food-safe https://www.wisebond.com/blogs/epoxy-blog/is-epoxy-food-safe
bee_rider 2y ago
I’m always worried about food-safety and Amazon. They don’t have very good control over their inventory, right?

thot_experiment 2y ago

I recently broke a piece of glassware that had been with me for over a decade. I have all the pieces and I'm wondering if it's possible to stick it in a kiln and run a heat cycle that will cause all the cracks to flow together without deforming the shape, and barring that if there's a thin gold glue I could use to do some approximation of this technique but with cracks that are essentially zero width.

throwup238 2y ago
A very skilled glassmaker might be able to fuse the pieces together by heating the edges and pushing them together if the piece is simple enough but in general, no. That's why it's called glass blowing: the air pressure is what gives the glass form while it cools and vitrifies.
chris1993 2y ago
The BBC “repair shop” show recently (last year?) had an episode repairing a shattered vase with some specialist glass repair glue, so you can probably find some for this.
hcrean 2y ago
There is a method where you piece the glass together supported in investment, (a type of ceramic casting plaster), by building it up in layers. You tightly pack it and put it in the kiln, the investment holds the shape of the object when it melts. This is a very advanced and difficult method of glass re-forming.
Baeocystin 2y ago
The short answer is no. You will not get fusion without slump. That being said, there are excellent, optically-clear, UV stable epoxies that are made for this problem. Hxtal is the go-to for most. https://www.lakesidepottery.com/HTML%20Text/Tips/Hxtal-NYL-instructions-glass-epoxy.htm https://www.lakesidepottery.com/HTML%20Text/Tips/Hxtal-NYL-i... It is very thin, and will happily wick in and fill cracks. Often the join is completely invisible. The downside is that the cure time is on the order of 1-2 weeks. It does take a little practice to use effectively, and it's worth trying on less-important projects first, but it's straightforward enough that you can expect success if you follow the directions carefully.

thingsilearned 2y ago

For those of you in the Bay Area there’s a great Kintsugi workshop that’s run out of the SF zen center almost weekly https://stonegoldcrafts.com/ https://stonegoldcrafts.com/ I got into Kintsugi when my toilet needed repair. It’s a rewarding craft https://thingsilearned.com/things/my-kintsugi-toilet/ https://thingsilearned.com/things/my-kintsugi-toilet/

avtar 2y ago
For those in Toronto :) https://introjapan.ca/inperson-classes/ https://introjapan.ca/inperson-classes/ No affiliation. I gifted my partner an intro workshop pass and she's been returning for more classes since then.
- criddell 2y ago
  How do you discover classes like this? Are there city-specific guides to interesting classes and seminars that you can take?
  - mholt 2y ago
    I'm also looking. The University of Utah has a random one-off kintsugi course this fall but I think it's full already.
  - avtar 2y ago
    I wish I could offer something more useful, but in this case her birthday was fast approaching and I remembered her bringing up Kintsugi in a conversation. I did a search for "kintsugi toronto" and found that teacher's site on the first results page. Back in the day I would have browsed craigslist, but unfortunately it's not as popular here anymore.
kelnos 2y ago
I've attended one of those at the Zen Center! My partner took me to one as a birthday present last year. She ended up being kinda frustrated with the process, but I found it soothing and relaxing, and left happy and contented. The guy running the workshop had us use epoxy and not urushi powder (not surprising; I'm sure all of us would have ended up with severe skin irritation otherwise). The article mentions concerns about food safety; IIRC we were told that the epoxy we were using in the workshop was not food safe, but that it's easy to acquire food-safe versions of it. We also didn't do this in anywhere near as many steps, with as many different treatments for different sizes/shapes of damage. Ultimately we fully repaired a piece in a couple hours, not the several months that the article author took to do it right. (And the extra care and use of the proper materials shows; the final repaired alligator mug from the article looks orders of magnitude better than my work.)

JSR_FDED 2y ago

This is super inspiring and the end result is amazing, congratulations!

kelnos 2y ago

> I knocked it off the kitchen counter and, giving into the idiotic reflex of trying to catch it with my foot, kicked it into the wall instead Not idiotic! I've saved more things than I've further damaged by doing this.

sunaookami 2y ago
Unless you are dropping a knife ;)
- mauvehaus 2y ago
  Or the business end of a blender. Or a big-ass chisel. Not hypotheticals, either of those, and not me.
  - smeej 2y ago
    I have a chisel scar on my hand that I call my "get down and move the damn ladder" reminder scar.
- jen729w 2y ago
  I’ve done this with a new and thus terribly sharp knife. I’d bought it for my mate, so when I knocked it off the bench my reaction was oh no! damage! catch! The kitchen looked like a scene from Kill Bill. Perfect blood spray in an arc across the wall. This mate lived with me at the time. And he was a nurse. He came home from his shift about half an hour later and I told him, sorry man, but you’re driving me straight back to the hospital. I’m lucky to still have total use of my right middle finger.
- namibj 2y ago
  That's why you keep a second mode trained that instead makes you jump away from the uncontrolled blade.
- smrq 2y ago
  Once, many years ago, I dropped a knife and caught it, fortunately by the handle. I felt very stupid for the obvious reason, but my cat was by my feet at the time--so I'm not even sure it was the wrong thing to do. Well, crisis averted, one way or another...

giraffe_lady 2y ago

This is really great results for an early project, none of my first few came out anywhere near so good. I've been doing traditional kintsugi for about twelve years, a couple hundred successful repairs. Though when I started there was very little instruction or english-language resources available. It's become pretty popular for obvious reasons which is great for people getting into it now. It remains probably the most difficult and frustrating skill I've ever learned. It's really hard to communicate just how meticulous, near-impossible some of the joins can be. There is a huge variety of technique and nuance to learn about different media and lacquer ratios for different kinds of joins & fills and it all needs to be done by intuition and experience. And then the medium has no holding power until the curing process is well underway. So you need a lot of creativity to come up with a scaffolding system, pretty much completely unique to each project. Any problem after applying lacquer means hours of careful filing and rework, and more days or weeks of curing. An edge-of-my-skill repair on a complete shatter takes about 100 hours spread out over 2-3 months. Even just an ideal three piece clean break is easily 8-10 hours and a handful of weeks.

fellerts 2y ago
Thank you for the kind words! I've not even scratched the surface of kintsugi of course, but the little I've learned agrees very much with what you say. It's a true test of patience. Are you entirely self-taught then, or did you find a mentor?
- giraffe_lady 2y ago
  Almost entirely self taught. I've got a few other practitioners I've asked for advice over the years but no one who really had guidance over my learning the way a mentor would. Early on I got most of my info from the newberry library. It had a collection of illustrations and manuals donated from a defunct lacquerworks museum in japan, for some reason. They had someone around who even helped with a lot of translation for free which was a major help. All this stuff is available and better explained on youtube now though.
cafebee 2y ago
I’m working on a shattered teapot and am finding the scaffolding part very difficult. Any tips on holding pieces in place that you’d be willing to share?

talkingtab 2y ago

Danger!!! Urushi is basically poison oak/poison ivy sap. Not quite the same, but in that family and with the same effects. Not to scare you off, but if you are interested in this, imagine all the things that can go wrong from if you were to get a tube of poison ivy sap and then do things with it. That said, Urushi is great and the number of things you can do with it is truly amazing. Just don't do it rashly.

smoyer 2y ago
> rashly Good one!
userbinator 2y ago
Most other adhesives and epoxies are also quite toxic when not cured.
- LoganDark 2y ago
  Even if you're not allergic the first time you use them, you can become allergic.
b112 2y ago
Sir...sir! This is hacker news! It's not some place to say somthong punny! What are you, The Punisher?

serf 2y ago

aside from 'the craft' and tradition of the process, is there any real benefit to using legitimate urushiol? there are lots of bonding agents and epoxies out there that are not urushi based , actually food safe, and just as easily doused in gold dust, and completely compatible with prepared ceramics.

mholt 2y ago
What's food-unsafe about cured urushi?
- conkeisterdoor 2y ago
  I don't think the GP was implying that urushi isn't food safe, but rather that some epoxies aren't food safe
  - MBCook 2y ago
    The author of the peace also mentioned that while there are food safe epoxies they were worried that they may be less food safe than expected when used with high temperatures like tea or coffee as opposed to being used in a simple serving dish.
    - xipho 2y ago
      According to https://www.lakesidepottery.com/Pages/Pottery-tips/ceramic-repair-and-restoration-questions-and-answers.htm#Anchor-Questio-57445 https://www.lakesidepottery.com/Pages/Pottery-tips/ceramic-r... there are no food safe epoxies, including Kintsugi...
      - ryandamm 2y ago
        Certified food grade epoxies are used in industry all the time; in fact, some wine is aged in epoxy-coated concrete tanks, and the inside of soda cans these days includes a thin layer of food-grade epoxy. I will not fault anyone for not believing the certification, but I would personally want to see a more authoritative source than an undated ceramics FAQ. But this is just personal style! Being suspicious of regulatory thresholds is prudent. (And this FAQ has me wanting to revisit my priors and research this a little more specifically, because its assertions are plausible, but need sources or explanations or dates, for cross-checking. Food-grade epoxy I believe in would be a handy thing to have exist; I do have some certified food grade epoxy in my garage that I haven’t used for anything yet and I’d dislike downgrading it to just “epoxy.”)

mholt 2y ago

My wife recently got into kintsugi. She's learning the traditional method described here. I'm reading these comments with great interest and will be passing this onto her! Most of the methods taught in the US are "gold relief" methods, which is basically glue with golden pigment mixed in. It doesn't look great but is modern and quick. "Gold flush" methods take a bit more time and are more authentic, but still don't use the traditional materials shown in this article. Does anyone know where to get these traditional materials for use in classroom settings (i.e. in bulk, preferably discounted)? Not massive scale, just enough for a few classes. The kits have such a tiny amount and are so expensive, even a bulk discount of ~10-20% would be ideal.

yegle 2y ago

Apparently there's another styles of repairing ceramic/porcelain: https://zh.wikipedia.org/zh-hans/%E9%94%94%E7%93%B7 https://zh.wikipedia.org/zh-hans/%E9%94%94%E7%93%B7

modernpink 2y ago
Apparently, it was this Chinese method of repair that horrified the Japanese aesthetic sensibility [0] into creating kintsugi. [0] https://en.wikipedia.org/wiki/Kintsugi#Origin https://en.wikipedia.org/wiki/Kintsugi#Origin

vsgherzi 2y ago

wow it's beautiful. Amazing job. Can you still use it in a dishwasher or microwave?

giraffe_lady 2y ago
I have a bunch of kintsugi stuff in regular use so I can answer. Microwave is a definite no! It arcs, kind of like gold-rimmed plates would I guess. Dishwasher you can. The repair is really two parts: the bond that holds it together and the gold dust that covers the lacquer. The join bond can handle the dishwasher. The gold layer needs touchup every few years anyway, but it will need it a lot more often if it goes through the dishwasher regularly. Gold is expensive. There are some other ways of applying the gold that can hold up better, but they're less common.

dlbucci 2y ago

This is awesome! The handle on my favorite mug broke off recently. I tried super gluing it back on, but it broke off after a few trips through the dishwasher (hand washing got old). I was gonna try epoxy next, but I try to avoid that stank whenever I can. Maybe I'll give this a shot.

pjerem 2y ago
Repairing the handle can be dangerous. It means that your repair is going to support the entire weight of your mug + the (hot) liquid.

tern 2y ago

I tried to order a kit with urushi powder from Japan recently and they had to cancel the order, saying it was now illegal to import into the US

astrea 2y ago

I had no idea it was done with a resin.

dudeinjapan 2y ago

I repaired mine with glue

piyh 2y ago

I repaired my mug with epoxy and kept using it for years until the handle fractured at the same spot, dropped on my trackpad and shattered it. Now I get new mugs when one breaks.

AdamN 2y ago

Is there a place that can do this for me?

notdang 2y ago
If you are in US: https://www.lakesidepottery.com/Pages/ceramic-repair-and-restoration-request-form.html https://www.lakesidepottery.com/Pages/ceramic-repair-and-res...

silcoon 2y ago

Look better than new in my opinion

roywashere 2y ago

When I was a kid I had a mug with my name on it that was gifted to me. My mother broke the ear off at some point and decided to glue it back on. A week later she handed me a steaming hot cup of tea and the ear tore off and I got severe burns on my leg as a result. Not great. As a result I am a bit wary fixing stuff meant to contain hot liquids

pmarreck 2y ago
I think anyone would after that experience! Yikes!

infecto 2y ago

Is it a good idea to use these as drinking vessels after repair? I always assumed the risk was too great. Even if you use some sort of epoxy over it, I would be concerned with contamination from the cracks not being fully sealed.

1970-01-01 2y ago

This is once again a perfect use case for cyanoacrylate. There's FDA approved, food-safe brands that will simply allow you to rebuild every fragment into the cup. It will also cure into ceramic in under a minute. I say this because I've done it. You're wasting time and energy using any other method.

akpa1 2y ago
I suppose it comes down to if you're purely in it for utility or if you're trying to repair this thing of yours precisely because it's this thing of yours. I'd be far more inclined to go to the lengths discussed in the article for a precious mug that I've used for a decade than I would for a mug I'd had for two, even if I'd still want to repair both out of thriftiness. It's a labour of love.
JoBrad 2y ago
Honestly, using CA is what I and many other folks would use, in this situation. I’m a huge fan of J-B Weld’s Superweld light-activated glue. In the right lighting, you can see the steam puff from the glue when you activate it. But OP’s process brings to mind the way we remember things: by reliving them in such a way that can (and usually does) produce a unique and slightly different product from the original. It’s the investment of time, thought, and love that makes this process more desirable. I’m reminded of a recent comment thread on Jaloponik, where some great heads were talking about just _why_ the fact that anyone can go 0-60 in less than 4 seconds isn’t actually a great as it seemed to be. I’m a nutshell it came down to the fact that this used to be the product of untold hours spent learning and iterating to eke out tenths of a second, over time, to finally reach that level. Admittedly it smacks of gatekeeping, but there is a fine line between gatekeeping and rewarding true mastery of an art.
bee_rider 2y ago
Does it look nice? The aesthetic is part of the whole thing, I think.

AJRF 2y ago

I think i'll try do this next time I smash a mug (maybe avoiding the Urushi lacquer as others have mentioned in this thread). It gives the mug so much character, looks better than before, and for sure it will be a conversation starter!

oofabz 2y ago

This mug is well on its way to becoming a tsukumogami.

bqmjjx0kac 2y ago

Did anyone else notice they pixelated their fingerprint in the "goldfinger" photo? 10/10 points for opsec.

fellerts 2y ago
I was waiting for someone to notice that. Good eye!

asshatdev 2y ago

[flagged]

coolspot 2y ago
It is too obvious what you’re trying to do.

hoseja 2y ago

I was somewhat disappointed when I learned this is not, in fact, done with a gold-based solder.

Talkative32 2y ago

[flagged]

phillias 2y ago

ITS POISON IVY! Do not breath in that stuff! I ended up the hospital with my face all bloated. No kidding. Japanese harvest from the urushi tree containing urison the irritant in poison ivy! I think they get off on shipping this stuff to American's laughing at them.