So this is a picture of what my kiln will be made inside. It's a 4000 lb rated industrial wire basket. I will be making a basket lid for the top and cutting a few holes for the stack and burner ports. I could easily make an updraft kiln out of this, but at this time I've decided to make the first fiber version a down draft with a short fiber stack. It will be lined in the bottom with a few layers of ceramic fiber paper 1/8 inch thick, and a layer of insulating fire brick. The walls will be constructed of 3 inches of fiber and hand made refractory ceramic buttons, held in pace with Kanthal A-1 wire.
The hotface of this kiln will be 1" layer of 2600 degree blanket made by Thermal Ceramics called Cerachem. The backer is 2" layer of 2300 degree blanket made by Harbison Walker. Both of the US companies produce superior and reliable products. I chose blanket for my kiln because of it's ease of construction.
The links below are to the two companies I purchase refractory products from. The top link is a pdf of the Thermal Ceramics blanket, and the other is the history of Harbison Walker (ANH), because their data sheets are not available to the public. None the less ANH is a great company, the sales staff at the Clackamas distribution center will bend over backwards to help meet your refractory needs.
http://www.barteltinsulation.com/pdfs/CERAMICBLANKET.pdf
http://www.hwr.com/EEC/Incineration/HWRHistory.asp
The buttons will be fireclay mixed with Mulcoa 40 grog (3X8 and 35 mesh) and some ball clay. Somewhere around 50% fireclay, 40% Grog, 10% Ball clay will be the mixture. I'm making a small mold to pound them into so I can pop out the buttons and fire them off easily and uniformly with good density and strength.
I did a lot of research on wire to hold these in place. This kiln will primarily be for cone 6 however I will end up doing cone 10 now and again for specific things such as the ceramic buttons. Maybe some other refractory items for my studio such as saggars, tiles etc. I may also make some parts for an outdoor oven which my mom is building this summer. So the wire must be able to withstand 2400 or so just to make sure. Most Nichrome wire will not withstand above cone 6 for very long. The Kanthal A-1 is a proven material for electric kiln elements for high fire even up to cone 11, 12 and will easily withstand my kiln temps.
Originally I had planned on buying a cheap wire feed welder from Harbor Freight and welding together some round steel rod making myself a box. When I found the one similar to the picture above the price was hands down better than all the long hours in the welding booth. I picked mine up used, but couldn't find any good ones locally and had to pay for shipping from back east. All in all it was still worth it getting me two huge baskets 44X55X44 for 65 each, plus shipping of 200. Altogether 330 bucks and all I have to do is fashion a lid and I'm done. Not to mention there is no worry about the strength of the material because it's an industrial quality basket rated at 4000 lbs. Another reason I chose this route is because I am still a renter and will be moving. Even though this is a heavy basket it can be moved even once the kiln is completed. One better plan is to build the kiln on the back of a trailer, which still might happen if I have the cash. I want to make sure I don't short myself before getting my burners completed first.
This brings me to the burners. I've decided to experiment with a large ventilation blower. It's a fully adjustable inline centrifugal blower made for industrial ventilation. It blows 450 cfm maximum which is more than enough. I'm going to try and rig up two burners to the same blower because this thing should have the power. I will have to build a small sheet metal splitter box that merge the 6" duct with two smaller burner pipes. I've decided to go with a small heated metal pail of about 1 gallon or so in size for the oil. I going to install a small heater either under it or inside it with which to heat the oil. The oil lines will not have far to travel this way and there will not be too much oil close to the fire. The entire apparatus will be strapped to a cart or hand truck for easy storage in my garage when not in use. I'm going to install a small port in the splitter box and a butterfly valve in which I can block off the blower and send some LPG down the burners to preheat before igniting the oil. This is all an unproven, untested system that I've never seen used before so we'll find out if it even works.
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