Recently Arnold from Paragon has been experimenting with a microwave kiln, which fits into a standard microwave oven. The kiln fires so rapidly that after five minutes, there is barely enough time for the outer surface of the kiln to become warm. Meanwhile, the orange, glowing kiln interior is hot enough to fuse glass.
Arnold's notes:
I have had consistent firing results with this kiln by checking the glass visually before it has fused completely. That is the method I have used for years in firing the little Paragon QuikFire kiln.
The microwave kiln is very difficult to fire by recommended time alone. This is because microwave ovens of the same wattage can have different firing times. Also, firing times can vary even in the same oven. One afternoon, the firing time was 10 minutes. The next morning in the same microwave oven, it was 5 minutes, 30 seconds. This was due to voltage fluctuation. Here is method I use to fire the kiln:
- Set the microwave timer for a longer period than you will need. If firings take about 5 minutes, set the timer for 6 or 7.
- Load the oven. Press Start. After a few minutes, open the door and lift the kiln top an inch for a second or two. Lower the top. Close the door and press Start again. (Note: You must wear clear safety glasses to check the glass. That is essential. Also, stay about an arm's length away from the kiln while you check the glass.)
- A minute later (or 30 seconds, depending on how far along the glass has heated), repeat the above. As the glass gets closer and closer to final fusing, check it more often. When the glass is done and you remove the kiln from the microwave, write down the time shown in the display window. Subtract that time from the number of minutes you started with. That is your total firing time.
- I have found that heat distribution varies inside the kiln unless you use the oven's turntable. If you do not use the turntable because the vibration and movement shifts the glass pieces, then fire only one or two pieces at a time.
