The one stop corn starch treatment topic!
12 posts • Page 1 of 1
The one stop corn starch treatment topic!
Originally this was presribed for Hagi-yaki, however there has been some success with other yaki as well.
And it seems we always have a hard time locating these discussions as they are often deep in some topic.
So, discuss your treatments here ... and problems as well.
And it seems we always have a hard time locating these discussions as they are often deep in some topic.
So, discuss your treatments here ... and problems as well.
Corn starch is not just for cooking anymore ...![]()
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Chip - Moderator
- Posts: 20910
- Joined: Apr 22nd, '
- Location: Back in the TeaCave atop Mt. Fuji
Re: The one stop corn starch treatment topic!
I posted earlier this year about a leak in a bizen piece that I had, and I used the cornstarch method to fix the leak.
My piece was a mizusashi, which is basically a large (~0.5 gallon) jug.
From what I recall, I added warm (say 150F) water to the pot -- I knew the leak was on the bottom, so I didn't have to add a lot -- just enough so I knew the entirety of the leak had contact w/ the water. Then I added a scoop or two of cornstarch and swirled it around a bit (a lot of it did not dissolve). I let it sit for about 30 minutes. Then I emptied it out and rinsed it with cold water a couple of times.
I think I had to repeat this 2, *maybe* 3 times. I vaguely recall that I only did the treatment once, and noticed the leak was still there (though definitely smaller). So I did the treatment again -- and maybe that's when I did it twice, just to plug it up for good.
Haven't had a problem since then, and it's been about 5 months and I've re-filled the mizusashi many, many times with fresh water.
My piece was a mizusashi, which is basically a large (~0.5 gallon) jug.
From what I recall, I added warm (say 150F) water to the pot -- I knew the leak was on the bottom, so I didn't have to add a lot -- just enough so I knew the entirety of the leak had contact w/ the water. Then I added a scoop or two of cornstarch and swirled it around a bit (a lot of it did not dissolve). I let it sit for about 30 minutes. Then I emptied it out and rinsed it with cold water a couple of times.
I think I had to repeat this 2, *maybe* 3 times. I vaguely recall that I only did the treatment once, and noticed the leak was still there (though definitely smaller). So I did the treatment again -- and maybe that's when I did it twice, just to plug it up for good.
Haven't had a problem since then, and it's been about 5 months and I've re-filled the mizusashi many, many times with fresh water.
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Drax - Posts: 2387
- Joined: Oct 16th, '
- Location: Arlington, VA
Re: The one stop corn starch treatment topic!
I had complete satisfaction using the cornstarch treatment with an old Hagi chawan which used to be a heavy leaker.
I alternated a mix of cornstrach with cold and boiling water. It took a few times till the leak completely stopped.
If only it could be that simple to fix leaks at home...
I alternated a mix of cornstrach with cold and boiling water. It took a few times till the leak completely stopped.
If only it could be that simple to fix leaks at home...
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David R. - Posts: 1074
- Joined: Oct 6th, '0
- Location: France
Re: The one stop corn starch treatment topic!
This is what seemed to work pretty nicely for a really major leaker. It was a Shibuya Deishi Biwa wan, it would almost completely empty in minutes. You could see the water coming out of the "pores." I thought, nothing can fix this one.
Dissolve 1 TBS of corn starch in around 8 ounces cold water. Bring this to a boil and the liquid clears, stirring quite frequently.
Pour the slurry into your leaker
The leaking should slow, just keep filling til the leaking appears to virtually stop
Allow the slurry to cool for several hours
Pour the slurry away and allow the cup to air dry w/o rinsing, and let sit overnight or longer
Repeatedly pour hot water into the cup to dissolve the surface dried up corn starch, wiping with a soft cloth, etc.
After you removed all the cornstarch from the surface, allow to cool again, then test with hot water
Repeat if needed, and you can increase the concentration
Interestingly, the cornstarch might eventually come out to the exterior surface after many many uses, only in the case of extreme leakers. When this happened, I soaked the cup in in hot water and then poured hot water into the cup several times until i was pretty certain I had gotten much of it out. The cup actually leaked, though much much slower than before.
I then did one treatment with cornstarch, but since it had barely leaked, the problem never repeated.
Dissolve 1 TBS of corn starch in around 8 ounces cold water. Bring this to a boil and the liquid clears, stirring quite frequently.
Pour the slurry into your leaker
The leaking should slow, just keep filling til the leaking appears to virtually stop
Allow the slurry to cool for several hours
Pour the slurry away and allow the cup to air dry w/o rinsing, and let sit overnight or longer
Repeatedly pour hot water into the cup to dissolve the surface dried up corn starch, wiping with a soft cloth, etc.
After you removed all the cornstarch from the surface, allow to cool again, then test with hot water
Repeat if needed, and you can increase the concentration
Interestingly, the cornstarch might eventually come out to the exterior surface after many many uses, only in the case of extreme leakers. When this happened, I soaked the cup in in hot water and then poured hot water into the cup several times until i was pretty certain I had gotten much of it out. The cup actually leaked, though much much slower than before.
I then did one treatment with cornstarch, but since it had barely leaked, the problem never repeated.
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Chip - Moderator
- Posts: 20910
- Joined: Apr 22nd, '
- Location: Back in the TeaCave atop Mt. Fuji
The one stop corn starch treatment topic!
I've done two cornstarch treatments per the previous post directions on my new tea tray and it's still leaking readily. Any suggestions on varying the treatment to give more robust results, e.g., higher concentration of cornstarch, or lower (wondering here if pouring it in already thickened might decrease the penetration of tiny pores?), or optimizing setting/cooling time?
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debunix - Posts: 3963
- Joined: Jan 10th, '
- Location: Los Angeles, CA
Re: The one stop corn starch treatment topic!
Wow. That is a bummer. You can always increase concentration. You can also try filling with strong tea or cheap Matcha. You could also try rubbing in dry corn starch, then fill with slurry.
These include some guesses. Good luck and please report back.
These include some guesses. Good luck and please report back.
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Chip - Moderator
- Posts: 20910
- Joined: Apr 22nd, '
- Location: Back in the TeaCave atop Mt. Fuji
Re: The one stop corn starch treatment topic!
Hello,
I'm new around here & cracked this teacup last night. I think it's older, it might be hard to see but the base color is grey-ish. This cup leaks now, when I added hot water last night I heard very faint tinkling or bell-like sounds which I attributed to my imagination. Guess not.
Since this cup is not just leaking, it's cracked, would the corn starch treatment work? Or is there something else I could try so I could keep using it?
TIA--
Kathy Marie
I'm new around here & cracked this teacup last night. I think it's older, it might be hard to see but the base color is grey-ish. This cup leaks now, when I added hot water last night I heard very faint tinkling or bell-like sounds which I attributed to my imagination. Guess not.
Since this cup is not just leaking, it's cracked, would the corn starch treatment work? Or is there something else I could try so I could keep using it?
TIA--
Kathy Marie
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- The crack from the outside
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- The crack from the inside
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Kathy Marie - Posts: 22
- Joined: Aug 30th, '
- Location: Madison, Wisconsin
Re: The one stop corn starch treatment topic!
Here is why I want to keep using the cup--I think it's beautiful, I just love looking at it. Thanks for your help! Kathy
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- cropDSC06467.jpg (101.03 KiB) Viewed 626 times
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- cropDSC06466.jpg (98.99 KiB) Viewed 626 times
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Kathy Marie - Posts: 22
- Joined: Aug 30th, '
- Location: Madison, Wisconsin
Re: The one stop corn starch treatment topic!
I'd be worried about that coming apart in my hands when full of hot tea, with a full-thickness crack like that.
If it broke a little more definitively, you could certainly try a quite solid repair like in this thread.
If it broke a little more definitively, you could certainly try a quite solid repair like in this thread.
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debunix - Posts: 3963
- Joined: Jan 10th, '
- Location: Los Angeles, CA
Re: The one stop corn starch treatment topic!
Thanks debunix! I hadn't thought about the possibility of the cup actually breaking. I'll try a test tonight, first wamring it up with hot water from the tap and then adding brewing water.
Will report back,
Kathy Marie
Will report back,
Kathy Marie
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Kathy Marie - Posts: 22
- Joined: Aug 30th, '
- Location: Madison, Wisconsin
Re: The one stop corn starch treatment topic!
The dreaded "chinking." Too bad, nice momiji motif!
If you can feel any wiggle when applying reverse force on the two sides of the crack ... especially near the top ... then the cornstarch treament will likely not help much though perhaps with frequent retreatings?
If you stick to drinking greens with it, perhaps it is worth the risk. At least then you are less likely to scald yourself in the event of complete failure. Plus the lower temps are less likely to further the cracking.
If you can feel any wiggle when applying reverse force on the two sides of the crack ... especially near the top ... then the cornstarch treament will likely not help much though perhaps with frequent retreatings?
If you stick to drinking greens with it, perhaps it is worth the risk. At least then you are less likely to scald yourself in the event of complete failure. Plus the lower temps are less likely to further the cracking.
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Chip - Moderator
- Posts: 20910
- Joined: Apr 22nd, '
- Location: Back in the TeaCave atop Mt. Fuji
Re: The one stop corn starch treatment topic!
Hi, Chip! Well, the cup held together fine even though I didn't warm it up that much before filling with water straight out of the kettle. It may have leaked a bit but it's hard to tell (it was in the sink in case it broke.) After it cooled down there was a place where cornstarch came out of the crack but it was _very_ minor.
And I tried wiggling the crack like you suggested and it held firm! That surprised me.
I'll try the "heat challenge" a couple more times and if it still holds together I think I'll try using it. What can I say, I'm a sucker for pretty!
I just think it *adds* something when you drink your tea from a lovely cup.
About using this cup for green teas, I'm not brewing my greens that far from boiling. For cheap greens you want the water boiling, right?
I accidentally made a pot that turned out *wonderfully* from kodacha I got from the grocery store. I've tried 4X so far with the same tea from the same jar, and I still can't get that flavor back. That tea was so sweet you'd think it had sugar added, but the funny thing was it was the second steeping and I didn't notice anything special about the first.
Kathy Marie
And I tried wiggling the crack like you suggested and it held firm! That surprised me.
I'll try the "heat challenge" a couple more times and if it still holds together I think I'll try using it. What can I say, I'm a sucker for pretty!
About using this cup for green teas, I'm not brewing my greens that far from boiling. For cheap greens you want the water boiling, right?
I accidentally made a pot that turned out *wonderfully* from kodacha I got from the grocery store. I've tried 4X so far with the same tea from the same jar, and I still can't get that flavor back. That tea was so sweet you'd think it had sugar added, but the funny thing was it was the second steeping and I didn't notice anything special about the first.
Kathy Marie
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Kathy Marie - Posts: 22
- Joined: Aug 30th, '
- Location: Madison, Wisconsin
12 posts • Page 1 of 1