A hairline crack

[ShuShu]

Just saw a hairline crack on the lid of one of my pots. Is there anything I can do to prevent this from worsening?

10065C4A-337A-4044-935C-2389611247E1.jpeg (181.16 KiB) Viewed 18748 times

457889AF-F63B-4EB3-8715-93D17634BFA9.jpeg (137.66 KiB) Viewed 18748 times

[Chadrinkincat]

You could have it stapled but it would probably cost $100-150. I'd recommend just leaving it as is. You can easily epoxy it back together if it eventually breaks.

[Bok]

and maybe refrain from pouring water over the lid as some people do.

[tealifehk]

I would epoxy it on the top, but not the bottom, using JB Weld

[Fuut]

I've always been hesitant to use epoxy or 2 material bonding agents on ceramics i actually use. Never quite comfortable to use something that gets hot and moist and then drinking from it. On the other hand i am comfortable using pieces with kintsugi. Anyone actually know what happens to the epoxy when it gets hot?

[Bok]

I've always been hesitant to use epoxy or 2 material bonding agents on ceramics i actually use. Never quite comfortable to use something that gets hot and moist and then drinking from it. On the other hand i am comfortable using pieces with kintsugi. Anyone actually know what happens to the epoxy when it gets hot?

If I am not wrong, only the traditional way of kintsugi and the used materials are safe. Anything “modern” less so...

Otherwise you need to procure specialised food safe and heat resistant products.

[Bok]

I would just carefully use it and then when it really breaks in two you can still find a solution

[ShuShu]

I would just carefully use it and then when it really breaks in two you can still find a solution

Thanks, everyone... I hope it won't break... I will let it rest.. I don't drink much roasted oolong anyways these days so no real harm (though the 20% sale at FloatingLeaves is kinda appealing)

[tealifehk]

MarshalN collects Japanese antiques: he said kintsugi'd items aren't meant to be used again. I told him I was served salad (shredded cabbage) on a kintsugi'd plate at a fancy tonkatsu place in Tokyo and he was very surprised and said it really shouldn't be done.

[ShuShu]

MarshalN collects Japanese antiques: he said kintsugi'd items aren't meant to be used again. I told him I was served salad (shredded cabbage) on a kintsugi'd plate at a fancy tonkatsu place in Tokyo and he was very surprised and said it really shouldn't be done.

Because of the materials used in a K repair? Perhaps there are non-toxic ones?

[.m.]

I've always been hesitant to use epoxy or 2 material bonding agents on ceramics i actually use. Never quite comfortable to use something that gets hot and moist and then drinking from it. On the other hand i am comfortable using pieces with kintsugi. Anyone actually know what happens to the epoxy when it gets hot?

If I am not wrong, only the traditional way of kintsugi and the used materials are safe. Anything “modern” less so...
Otherwise you need to procure specialised food safe and heat resistant products.

I've been google researching this in the past, these were my conclusions:
Well cured urushi laquer is neither more heat resistant nor more chemical resistant than a well cured epoxy. In the temperatures around 100degC in a non-acidic environment they both should be relatively food "safe". In fact, epoxy has been used for lining food cans, and has been FDA approved for that. Of course, it does contain BPAs, and it likely leaches them into canned tomatoes. And yes, there are several different epoxy formulas, some more heat resistant, some more chemical resistant, some perhaps BPA free, but, as far as i know, none that is 100% food safe. And while I would absolutely prefer to use urushi lacquer and traditional kintsugi over epoxy, and would feel much better about it, I would not think that it would be any "safer".
Going back to the original question, i completely agree with Chadrinkincat:

You could have it stapled but it would probably cost $100-150. I'd recommend just leaving it as is. You can easily epoxy it back together if it eventually breaks.

[Baisao]

MarshalN collects Japanese antiques: he said kintsugi'd items aren't meant to be used again. I told him I was served salad (shredded cabbage) on a kintsugi'd plate at a fancy tonkatsu place in Tokyo and he was very surprised and said it really shouldn't be done.

This is along my line of thinking as well, but mostly because urushi doesn’t do well with heat and humidity, in my experience, and if not properly cured the urishiol could cause dermatitis. I’ve been surprised that people use kintsugi teapots. Riveted pots seem like a better option if the intent is to continue using them.

[pedant]

I've always been hesitant to use epoxy or 2 material bonding agents on ceramics i actually use. Never quite comfortable to use something that gets hot and moist and then drinking from it. On the other hand i am comfortable using pieces with kintsugi. Anyone actually know what happens to the epoxy when it gets hot?

If I am not wrong, only the traditional way of kintsugi and the used materials are safe. Anything “modern” less so...
Otherwise you need to procure specialised food safe and heat resistant products.

I've been google researching this in the past, these were my conclusions:
Well cured urushi laquer is neither more heat resistant nor more chemical resistant than a well cured epoxy. In the temperatures around 100degC in a non-acidic environment they both should be relatively food "safe". In fact, epoxy has been used for lining food cans, and has been FDA approved for that. Of course, it does contain BPAs, and it likely leaches them into canned tomatoes. And yes, there are several different epoxy formulas, some more heat resistant, some more chemical resistant, some perhaps BPA free, but, as far as i know, none that is 100% food safe. And while I would absolutely prefer to use urushi lacquer and traditional kintsugi over epoxy, and would feel much better about it, I would not think that it would be any "safer".
Going back to the original question, i completely agree with Chadrinkincat:

You could have it stapled but it would probably cost $100-150. I'd recommend just leaving it as is. You can easily epoxy it back together if it eventually breaks.

correct. i think that pro-level kintsugi is beautiful, but i'd just use a minimal amount of jbweld. less is more. for this use case, if you do it right, you should hardly even see it bleed out after pressing the workpieces together. this means that virtually none of it will be exposed to the inside of the pot. if and when it breaks, you can try applying a seriously thin bead to the upper (outer) part of the break instead of at the center. i'd use a small clamp like this or a thick rubberband that you find on supermarket broccoli. break a small plate (get one from goodwill?) and practice gluing it to get a feel for how little to use to minimize bleed.



but back to the original question of how to prevent crack propagation...
theoretical, but i'd look at the techniques used on car windshields. have you ever had a chip filled?
drill out a very small hole at the crack frontier and fill it with epoxy.
but would i do that? no.

[GaoShan]

Before I started on my exhaustive quest to find a good Taiwanese oolong pot, I bought this wood-fired teapot that I loved, but that broke during my first session with it. There are multiple hairline cracks through which water eventually seeps, and I was wondering if there was any way to repair this pot so it's still usable. I also wonder whether, even if I repair it, the pot will keep cracking because of issues with the clay/firing.

I think the drippy glaze is beautiful and would like to rehabilitate this pot, but have limited repair skills and don't want to waste time on something that can't be fixed.

Sorry for the bad pictures; I hope you can see where the cracks are.

image0.jpeg (63.04 KiB) Viewed 14096 times

image1.jpeg (55.31 KiB) Viewed 14096 times

image2.jpeg (58.07 KiB) Viewed 14096 times

[Baisao]

@GaoShan - is that crazing of the glaze or do the cracks go all the way through the clay body? (I guess if water eventually seeps then it is the clay)

I would expect crazing of the glaze as it will expand/contract at different rates, but the clay should be hardier.