Repurposing tsuchikabe clay

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Tora
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Repurposing tsuchikabe clay

Post by Tora »

I'm demolishing a couple feeble outbuildings with tsuchikabe earthen walls. It seems like a great material and I'm keeping some in rice bags To try on an earth oven and maybe to use for some adobe type interiors in future projects. The wife is not as keen as I on earthen walls and there is a lot of it so I'm wondering if there are other interesting or useful thing I might reuse said clay for or if I should just put it in a pile out back til I realize I should have kept it in better conditions.

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Re: Repurposing tsuchikabe clay

Post by Zasso Nouka »

Brett is probably the one to answer that for you, me I have no idea.

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Re: Repurposing tsuchikabe clay

Post by BrettRas »

Sounds like you've got good ideas for using the material, you'll likely need to adjust the mix a bit depending on how you want to use it. Being outbuildings, I guess they might only be rough finished (arakabe). Or do they have a nakanuri (sandy layer) finish over the thick base layer? If so you'll likely want to try to separate those layers and store them that way.

It certainly would be most convenient to store in bags if you've got the space, as you can put it to use rather quickly, but I think you'd be fine storing it outside too. After all, the earth originally came from outside! If you go with the pile method you'll probably want to add more straw and do another fermentation period depending on what use you eventually put it to.

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Re: Repurposing tsuchikabe clay

Post by Tora »

Thanks Brett. The walls on the out buildings are just one coat? With clay and straw. I've been putting it in old paper 30kg rice bags but they are heavy and take up a lot of space and I'm on bag #10 and am only finished with half of the smaller outbuilding. Plus the shed roof leaks... I plan to replace that but it seems like I've been working on repairing everything else but the house I set out to repair in the first place. I'm sure there is a metaphor about life in there but I'm too tired to find it now.

Any recommendations on a good way to remove the Sanu mica outer layer used on the interior house walls? I'm going to raise the door headers and replaster (keisohdo?) the interior walls if I ever get the outbuildings removed and the extension finished....

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Re: Repurposing tsuchikabe clay

Post by BrettRas »

The interior house walls are not earth walls then I take it?
Sanu mica (I'm not familiar with that?) over over drywall/cement board or something like that?

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Re: Repurposing tsuchikabe clay

Post by Tora »

Sorry, I can't type well with my thumbs. I meant a layer of "sand/mica" over the wattle and daub tsuchikabe (Arakane?). Or that's what it looked from examining the gaps along the posts, beams and headers. I haven't gotten around to removing any sections of the interior walls and they are all in good enough shape that i can't see how they are made from looking at broken/deteriorated areas. There are some areas where the earthen walls have separated from the posts, beams or headers due to sagging or slight tilting but it doesn't look too bad. I hope to have my friend who is a professional builder tend a look and not give me any bad news.

I also just realized I do not know how to talk about tsuchikabe in English....

Do you happen to know if the tsuchikabe clay similar to the clay used to make the old wood fired stoves(?) used in the old doma style kitchens?

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Re: Repurposing tsuchikabe clay

Post by BrettRas »

Ahh, right, ok. :)

I'd say it depends what kind of condition the surface is in, and how much work you are prepared to put into it.
I assume we are talking about a newer (relative to when the wall was first built) sand/mica finish layer and not the sandy nakanuri layer (sometimes walls were finished just to this layer).
If the sand layer seems like it will scrape off fairly easily, you can just do it with a trowel and likely wouldn't take that long. Wetting it down with a spray bottle will often help.

If that seems like its going to be difficult to do, and the sand layer is firmly attached to the layer beneath, then you can try just plastering right over the top of it. You'll need to do two layers, one will end up being a bit of a sand plaster mixture which will kind of hold everything together and then you can do a finishing coat over the top of that once the first layer has dried.

As for the kamado in doma kitchens and elsewhere, I have not yet tried my hand at making one.
However, I would say the earth from your walls would certainly come in handy when building the stove. You'll probably want to experiment with different mixes/consistencies of the clay/earth/sand/straw to see what blend seems to work best in your case.
I know the polished finish often seen is usually done with a different fine lime/clay mixture (Otsu), and from what I hear can demand a good deal of skill to make a really nice one. But you can finish it with many different methods.

Like many of these traditional items, things can vary from region to region. In the island here, I've come across kamado carved directly out of a conglomerate stone/earth found in the hillside. In my house, there is a newer (showa era) style tiled kamado made mostly of brick and the base is made from flat plates of hand cut sandstone. So there were certainly many methods/techniques in use.
It's one of the areas I'm certainly eager to learn more about.

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Re: Repurposing tsuchikabe clay

Post by Tora »

Thanks. It's helpful to hear more about the process from somebody who's been through it and understands it.

Not sure how much newer the sand layer might be. Walls in a couple rooms have been plastered over but not sure why. One room looks to be where the most moisture would be found in the house. Still haven't been under the house and am a little nervous about what I'll find!

I was considering filling the gaps between the earth walls and wood posts/etc. with a slightly moist paste/slurry of the old tsuchikabe or maybe plaster with a caulk gun. While rebuilding glass furnaces I
discovered you can take an empty silicon/etc. caulk tube, unscrew the tip, push out the bottom end with a long piece of wood or metal, clean out the tube and then reuse it. I wonder if a pastry bag like those used for decorating cakes ore filling cream pan pastries might also work and be easier to prepare.

Kamado is the word I was looking for. I'll ask a couple friends who are professional potters what they have to say about the clay.

Is there a good way to recognize if the nakanuri layer contains asbestos.?
Also, is there an ideal season for doing wall plaster?

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Re: Repurposing tsuchikabe clay

Post by BrettRas »

I'd recommend getting a good look under the house as soon as you can to know what you are dealing with.

The nakanuri layer would not have asbestos, it is made of clay/earth/sand/straw and would have been applied when originally making the wall.
A finishing layer above that applied more recently could include asbestos if it is the cottony/sparkly junk that was often used 25~50 years ago.
I believe there are some pictures of those types of wall materials in my kominka post.

Usually the gaps between the earth walls and posts would be filled with a nakanuri type sandy mix using a trowel. The sandy mix will not shrink/crack the way the straight aratsuchi would. You would want to avoid mixing it too slurry like to again avoid shrinking and cracking when drying.

You can then do a finishing plaster over that.

I try to avoid doing plastering when its too rainy as particularly with shikkui I've noticed that when it takes a long time to dry you can sometimes get a funny sheen on the finish.

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Re: Repurposing tsuchikabe clay

Post by Caleb Fuller »

Tora wrote: I also just realized I do not know how to talk about tsuchikabe in English....
In English it's called "wattle and daub". The wattle being the woven wooden lattice, and the daub being the earth mixture that is plastered on top. It was one of the most common construction methods for centuries, if not millennia, in Europe. The main differences, compared to Japan, are that in Europe the lattice is usually woven from willow or hazel, while in Japan bamboo strips are used. The European daub also often incorporates manure, which I think was rare in Japan.
:ugeek:

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