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kiln Answered

does anyone know how to build a kiln that could be used for firing and annealing glass? it must reach about 1100 degrees F i think. thanks!


try flame annealing, you can do it with a cool (gas rich, no oxygen) flame.

hey guys thanks so much for all ur responses! the kiln i am trying to build is smaller, for making beads, pendants, christmas ornaments etc. so basically the interior dimensions are like 8-12" for l, w, h. could this be done with heating coils, and if so what/where do i find them?

Electric stove, electric dryer, ceramic supply (kanthol wire)...I've seen plans (Popular Science? from 30's to 50's) on using iron and stainless wire, not sure what temps they reach.

It is not terribly expensive. It is difficult though. You need to decide the space you need and purchase sufficient fire brick to enclose it. construct the body and both mortar (with appropriate mortar) and strap the brick (steel strapping) tightly. Cut grooves inside to hold the heating elements. This is the difficult part... You need to run the heating elements while they are fully heated; Otherwise they will break. You purchase the heating elements according to length needed, resistance of the element and maximum temperature. This will take some calculation based on the specs of the element. Best to ask how to do this from the source you find for it. You can get away without temperature controls by having a hole in the kiln behind a small shelf. The hole is normally plugged with a fire brick "cork". You can buy temperature cones to set on the shelf. When they melt and fold over, you're at the target temperature and can remove the power.

Element wire only has to be hot to form after it's been used-new wire hasn't oxidized and gotten brittle. Temp controls are needed for annealing glass-it's just too picky about holding at the right temp. Heating elements can be estimated-but if you need to get specific (minimum) temps within certain time limits, you have to make sure that your element will get hot enough. "The Electric Kiln" by Harry Fraser goes over the calculations needed.

How much are you willing to spend? Electric, propane or natural gas? How many cubic feet? Can you build the temperature controller or will you need to buy it?

Glassblowing at Yahoo has some info, so do the Wet Canvas forum topics (if you can find them).

Building a kiln is pretty extensive. I saw in a video, in Mexico they piled rocks up heavily, and heated alot of them up in a fire-powered oven, and then they put the rocks in, and then the clay, and eventually it became fired.