Millard B.
Yamadori
I use an Olympic 40" x 30" x 29" cone 10 kiln. The largest pot I've made was a 38' x 27" x 4." oval . Big pots come with a slew of problems, first you have to have another set of hands with a strong back to flip the pot several times after it is formed to detail/patch imperfections, add feet, wire holes.... Making the form for the big pot was very time consuming, I cut over a hundred wall sections from 3/4" plywood, screwed them onto a smaller 3/4" plywood center anchor form, then applied Bondo to the spaces between the pieces, sanded, Bondo several times more to make the form as close to perfect as possible, then took this wooden/Bondo form placed it upside down on another piece of smooth 3/4" plywood, made a rectangle 5" tall form, cut more pieces to 45degree each corner, cut two pieces of 5/8" rebar drilled thru the long ends of the form sticking out 8" for flipping handles, . In hindsight I should have put Rust Kill on the rebar as it has rusted and is spalling and the cracking the plaster. Apply mold release, mix 80 lbs of Hydrocal plaster, then wait a week before removing the negative form. Then we had Miami Clay mix a special 1000 lb batch of clay with a substancial amount of Kyanite in the clay body. I still have the positive plaster form. Between cutting all the small wall sections, sanding, making the negative plaster form I invested over 100 hours labor. A straight sided oval or rectangle would have been less than a quarter of the labor. I really liked the outer re-curved strong out lip.
Two years ago I slabbed a 41" x 10" x 3" straight sided rectangle that was 1" longer than the inside of the kiln moist, between SLOW air drying and firing to cone 6 it finished at 37" long, it was the first pot I sold at the Bonsai Societies of Florida Memorial Holiday sale. If you are dead set on a particular size, shape pot I can make it as I do accept commissions-
When Miami Clay went belly up I switched the Kickwheel Pottery Supply in Stone Mountain Ga and bought 1000 lbs of Big Red, made a pot in the mold and fired it, about 6 hours after it hit cone 6 and started the cooling process I heard a loud CLINK, the pot split into two pieces like it was cut into with a table saw! Win some, Loose some.
Two years ago I slabbed a 41" x 10" x 3" straight sided rectangle that was 1" longer than the inside of the kiln moist, between SLOW air drying and firing to cone 6 it finished at 37" long, it was the first pot I sold at the Bonsai Societies of Florida Memorial Holiday sale. If you are dead set on a particular size, shape pot I can make it as I do accept commissions-
When Miami Clay went belly up I switched the Kickwheel Pottery Supply in Stone Mountain Ga and bought 1000 lbs of Big Red, made a pot in the mold and fired it, about 6 hours after it hit cone 6 and started the cooling process I heard a loud CLINK, the pot split into two pieces like it was cut into with a table saw! Win some, Loose some.
