The Education of a Bonsai Potter II
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StoneForest
Seedling
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roberthu, the only metal that can go into a kiln is high temp wire used specifically for that purpose. Even then I would never use it within a clay body... it would most certainly crack. Choosing a good strong dependable clay body for your building/firing conditions should minimize any problems with your pots.
Leo in N E Illinois
The Professor
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@W3rk & @roberthu
Armatures work well in concrete, especially the "no shrink" mortars and low shrink Portland Cement based concrete. In a concrete bonsai pot armatures, wire support and plastic "bow ties" all help with flexural strength. But in concrete no heat, and minimal shrinkage is normal, so these things work. You can't do the same in clay, were you are using temperatures hot enough to melt cast iron. Just does not work in fired pottery.
Yes, bonsai pots, especially larger size bonsai pots can be made from concrete. This is a common practice in southeast Asia, Indonesia and anywhere where bonsai tend to be larger specimens. If your pots are a meter or two in length or diameter, concrete becomes preferable over clay. Easier to work with at the very large sizes. China, Vietnam, Thailand, Malaysia, & Indonesia you will see many, many concrete bonsai pots. The do tend to be quite large, for large trees, but that is the style in those countries.
Armatures work well in concrete, especially the "no shrink" mortars and low shrink Portland Cement based concrete. In a concrete bonsai pot armatures, wire support and plastic "bow ties" all help with flexural strength. But in concrete no heat, and minimal shrinkage is normal, so these things work. You can't do the same in clay, were you are using temperatures hot enough to melt cast iron. Just does not work in fired pottery.
Yes, bonsai pots, especially larger size bonsai pots can be made from concrete. This is a common practice in southeast Asia, Indonesia and anywhere where bonsai tend to be larger specimens. If your pots are a meter or two in length or diameter, concrete becomes preferable over clay. Easier to work with at the very large sizes. China, Vietnam, Thailand, Malaysia, & Indonesia you will see many, many concrete bonsai pots. The do tend to be quite large, for large trees, but that is the style in those countries.
roberthu
Chumono
Thanks. I can't even imagine how much those huge pots weigh. I have see some in China before I came to the US. Those pots with soil and trees probably weighed over a ton.
That is a top quality pot. Handmade with Gyosan’s signature center drain. He makes some without that drain that are his “everyday” pots. This pot is suitable for top level shows. It’s also sturdy enough to be used as an everyday pot, but you would likely only use it for a special tree.
The “antique” pots began their life as “everyday” pots. Lol!!! And over time acquired the patina and age that makes them special.
Gaea's listener
Yamadori
It seems that number of tie- down holes is debatable and personal preference amongst you, bonsai artists. There seems to be no one correct answer, as there are many scenarios. I appreciate everyone's input, this has been super educational and interesting subject and I have learned a lot. As a result, I have experimented with bonsai pot structure using the suggested measurements to place the drainage holes. It is my first try and seems that I have miscalculated the measurements for the hole cutters and despite the best effort, they are not even. Something for me to work on mastering for sure: proper use of a ruler. Regardless of this, I am curious to ask: what do you think about this design? It is a wheel thrown and altered pot with slab body and feet. It has been so fun to make I'm considering making more, but this time cutting the holes before attaching the feet, this should solve my issue.
Gaea's listener
Yamadori
the clay shrinks as it fires, approximately 10-15% for Stoneware Cone 6 clay. Although there are heat resistant wires available, for the reasons of shrinking this would be challenging to calculate and fire together. If you put the wire in the clay, the shrinking of the clay will cause the structure to crack around the wires as it dries and gets fired. However, it would be possible to create holes for the wire to be added post firing and perhaps small amount of cement or pottery glue to insert it. I have considered this process for the garden fountains but have not actually tried it yet.
Gaea's listener
Yamadori
that is a lot of drainage. Signature fancy holes look fun
Gaea's listener
Yamadori
update on the pot: unglazed, red clay pot is enjoyed by a selection of local silver maple seedlings that I just put into a pot together. The maple grove is using it temporarily, but is having a good time.
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Gaea's listener
Yamadori
Really nice glaze. I don't much like green, but mixed with the blue it works well.
