It seems like it has taken forever to get here, but we have completed our first firing and it was a resounding success! I began glazing on Sunday, September 30 and Kim loaded the kiln on Thursday, October 4. We fired on the 5th and unloaded at nearly midnight on the 6th.

I have fired and loved my Geil kiln for the last 9 years and had not built a kiln for 30 years, so it was with some trepidation that I approached the kiln building project. The kiln I ended up building was a modified Minnesota Flat Top. The original plans for the MFT were for a cube shaped car kiln with liquid propane burners. I wanted a front loader that was taller and not so deep, so I did away with the car and designed it for 2 stacks of 14X28” shelves. Kim had 2 Ward power burners and we used them coming in from the back, placed on either side of the chimney. I built a movable door on barn door tracks out of soft brick.

One of the opportunities I have as I travel around the country teaching workshops is to collect lots of differing opinions. In my travels I have met several potters that use Nils Lou’s MFT design and without exception the seem to love how it fires.

Ironically, it still seems to still be a controversial design, with its flat roof and double venturi flue. Overall, I liked what I heard about his design, however, and decided to take a chance. I talked to Nils and he told me I should be able to build it tall and narrow without any detrimental effect on the evenness of firing.

From an aesthetic point arches are much more beautiful than flat tops, but we had lots of straights and no arch brick, so I decided to go with a flat roof. Based on my first experience building a flat top, however, my next kiln will have an arch. Although it might get easier with experience, for me it was just as difficult to build a flat roof than as it would have been to build an arch form, put in skew-backs, and lay up an arch.

Of course I have only fired it once and it is too early to draw conclusions, but my first impression was extremely positive. Nils claims that the double venturi flue evens out the firing, eliminating cold spots in front of the exit flue. I believe that this first firing was the most even firing of my career, with less that 1/2 cone variation anywhere in the kiln! With the Geil I was used to a cone to a cone and a half variation throughout the load, but that didn’t usually cause a problem with my glazes. Both of the kilns I fired for many years tended to be hottest in the middle of the load.

began to theorize last winter (all ceramic theories for me are continually evolving...) when I fired in Doug Jeppesen’s Alpine kilns at Waubonsee Community College, that using power burners offered a positive improvement for single firing. My theory says that during the burnout phase (1400 - 1800F) that it is possible to introduce an excess of oxygen into the chamber, which more effectively combines with the carbon in the clay, creating carbon dioxide. As the carbon dioxide vaporizes it leaves a clean body, eliminating the blistering and pinholing which can plague single fired pots. I do have to say that so far I haven’t noticed one pinhole on the pots that came out of the kiln last night...

 Well, enough about the first firing and kiln building and firing theory... It was a very good firing and I am thrilled to have it behind me!