I needed to be able to move my kiln to an area in a large framed garage that I am currently sharing with the father-in-law. Before and after the kiln is loaded I can move it easily to the location in the shop that has the 240 volt power source. This outlet is shared with the large compressor and welder. I used an old bed frame for the steel and welded four 2″ industrial casters on the legs.
I have been making homemade burners for 15 years so this one has been in the works for awhile. With this new kiln I really wanted to figure out how to build a primary air flap that was attached to the burner itself. I’ve seen other designs with air flaps attached with small screws tapped into the bottom of the pipe and the flap that swung to partially cover the air intake. I guess I didn’t really like that design… Call it aesthetics, call it stubbornness… Call it a glutton for punishment, I didn’t want those flaps.
After many false starts and failed attempts I decided on using a die to tool 9/16″ standard thread (NC–National Coarse) that I could attach a thin Jam nut with a circular sheet metal circle welded to it. By threading the nut up and down would increase or decrease the air gap just like a commercial burner.. Once those were in place I then went back and used a 1/4″ pipe thread die (NPT-National Pipe Thread) to enable the whole burner assembly to be tightened onto the 1/4″ Street Bend of the burner plumbing.. To come soon.
On this image notice that I had to weld the section of 1/4″ nipple to the piece of 1″ flat steel that will attach to the bottom of the Burner. This was my work around by not having a pipe vise.
The Peep Ports were made using small paper cups glued together. I wanted to shape the ports so the inside has a taper, in case the cone packs are not placed dead on. I made a form from 3/4″ plywood and used commercial insulating castable. Each port and plug was made from 2lbs of dry castable and 1 cup of water. Allowed to dry overnight and then the cups were removed and the formed cleaned up with sandpaper and in some cases a dremel. I filled the cups with wet clay to help hold their shape during the casting.
I have needed a new kiln for years. I knew this. One of the problems with being a potter is the need for such specialized equipment. To have a kiln more than a commercial electric model demands space and more importantly in my case, some semblance of geographic stability. The last five years has seen some of the biggest changes in my life, job, house, multiple states–the birth of my son’s. What I needed was a decent size kiln–one that I could finally finish larger platers and plates–that was fuel efficient, fired evenly, economical to build and most importantly: modular.
Kilns and modular are not things that go together in the same sentence very often. But this design fact was imparative for me. My family have moved three states in the last five years and I know we are not quite done yet. I need to be able to move this kiln with out the need of a fork lift and it’s own special truck. Thus the following design has emerged. A small scalable down draft gas kiln that will be loaded from the top. The lid will be lifted straight up via a counterweighted pulley system to limit the strain on both my back and the lid/frame of the kiln.
It started with designing the size of the kiln based around the position of the burners and the size of the shelves I’ll be using. For the burners, I will be building a modified version of what I have been firing with for the past 15 years. They are 9″ venturi style burners built from readily available black iron pipe and brass caps for the orifices. For many reasons I am building the frame so the flame will enter the bottom of the kiln unobstructed with the exit flue on the bottom rear of the first ring to create the downdraft.
At the time of writing this I have already finished welding the frame, laid out and mortared the floor. Finished the burner assembly and now I am starting to cut and lay out the brick for the “rings”. I am still in the designing phase of the chimney and chimney frame. I keep going back and forth whether or not to cast the chimney in sections or to make them out of brick. More on that later…