New brick bottle kiln. The 'Monster'

My latest clay furnace is a small bottle updraft named 'Monster' by my daughter after an energy drink she says it looks like.

Ive wanted to experiment with a different design, hoping to gain easier firings and higher temps.

Just a bunch of firebricks surrounding an old cut up 55 gallon barrell. That surrounded by red brick.

It took me only 4.5 hours to reach 2000'F, and it could have went further if I pushed it. May have went too hot for the clay I was using for the test bricks inside.

Looks to be a real improvement so far though. I will post the results soon.

I pressed out 12 clay bricks last week just for this test firing today. Finished drying them in my electric kiln last night.

Heres a peek inside at the end. See the brick slumped over. Got too hot I think. Gonna have to slow down this beast and run it to 1850 - 1900'F max.

Tennessee red clay test firing.

My wife and I went on vacation last week to the mountains of Gatlinburg, Tennessee. I gathered a sample of the well known local red clay to test once I got back home. I wanted to try it out to see how it compared to the clay from my back yard here in Indiana.


The differences in clay is most noticed by color from the iron oxides. Both types have it, but it is more obvious in states of the south. It may have to do with glaciers that overran the northern states like Indiana thousands of years ago.

I brought back several pounds of red clay from my vacation in a plastic tub for test firing.

The outer two are Tennessee red clay and the inner two are Indiana clay. Green unfired from the brick press. The sample clay is very sticky and plastic. It makes a nice unfired brick.

The brick on top is Pigeon Forge, Tennessee red clay. The other three are Flora, Indiana brown clay. Fired in the same kiln for 9 hrs to 1875deg F. Notice the difference in shrinkage.

Heres the address if you are interested in why some clays are so much more red than brown, yellow, or grey.

http://www.ga.nrcs.usda.gov/technical/soils/red.html