I'm finishing building my own kiln. I'll post some pictures when I'm done. It's a bell kiln with two bottoms which are on wheels. The hoist is tall
enough that I can work under the bell if I wish without bending over. The
interior dimensions are 52" x 52" x 17". I've got Joppa Glassworks elements on the sides and Duralite Quartz tube elements on top. There are dual controllers, one primary and one backup for thermal runaway shutdown. I'm using an Orton Autofire 2000 for the primary and a thermal controller from Omega Engineering as the backup. All relay's are mercury displacement. Total cost including all of the special stuff (hardware and tools) is about $6700. I've priced comperable sized commercial kilns on the market and they are 2x to 3x what I've spent and given all of the bells and whistles I've put on this thing I'm guessing that and exact feature equivalent would probably be 4x to 5x what I spent. I will grant that a cheaper version of what I've made could be done along with a heck of a lot more.
I took Larry's class in NM and it was a great class. Larry is quite knowledgeable and has given me great support after the fact.
It's a fun process but be prepared for a lot of work. It will also cost you more than what you think but that is ok. You will end up with what you really want in the end.
One place I can really recommend for all of that special hardware and things is McMaster-Carr. (
http://www.mcmaster.com/) They are a lot cheaper than Grainger and they ship everything to you in days. I would also strongly recommend that in your design, anything you use that is load bearing ie cables, pulleys, eyebolts, etc., you spend the extra dollars and get RATED hardware. Don't go and just get a bolt from Home Depot and not know it's rating. Falling bricks, steel and insualtion is not fun.
Anybody has any questions feel free to email me and I'll be glad to pass any tips/info on to you.
Phil