Wednesday, December 30, 2009

Microwave Kiln - QUESTIONS & ANSWERS - Part 5B

Hello Kate,

In response to your questions/comments let me address them one at a time as follows:
Q = Question
A = Answer
C = Comment
R = Response

Q: How is the microwave firing any better than a torch firing?
A: The microwave kiln was primarily created to fuse glass, enamel copper and fire ceramic bisque. Since its inception those like myself who are familiar with PMC or Art Clay Silver have taken the use of this unique piece of equipment to another level. Through all of my testing with and without inclusions of glass, stones, I have perfected a firing schedule that will allow silver clay to sinter. If a person is only wanting to fire metal clay than the choice would be a torch, but if they wanted to incorporate glass in their design than they would need the microwave kiln.

C: The firings do pollute the microwave, so you really need a separate oven for it, and then you need to buy the saggar, which has a tiny firing chamber.
R: Engineers who design the microwave kiln and writers of their documentation did not take into account that fiber paper and kiln wash does pollute the microwave oven and therefore tell individuals that it is okay to use the same oven. I always recommend a separate oven just for that reason and you are absolutely right.
Q: The saggar in this case is the microwave kiln itself and that is what is needed to fire jewelry design items in a microwave oven. The microwave kiln I distribute known as the MicrKiln, will accommodate up to (7) 1" square glass designs in a single firing. There are much larger microwave kilns but they are not being sold in the US today.

C: I am having trouble comprehending why this is .... useful
R: It is only useful if you want to do some of the techniques mentioned above and cannot afford a glass/ceramic kiln or just don't want to make that type of investment at this time.

Q: What is your annealing process for fusing glass?
A: I have a step-down schedule (annealing schedule) that I use that incorporates the use of the microwave oven's power levels in conjunctions with the appropriate allotted time in minutes and seconds. The holding time is also based on the thickness, size and type of glass being fused and whether or not it is being incorporated into metal clay.

C: I'm not grasping why this is a good idea.
R: It is only a good idea if you need a kiln to do some of the techniques mentioned earlier and can't afford a "real kiln." If someone is just wanting to fire metal clay without glass or sensitive firing inclusion than a torch is the way to go unless they are affair of using a torch. I have a few students that they are their spouse will not allow them to have a torch in the house.

I hope the information I have provided helps. The microwave kiln has gotten such a bad rap over the past two years do to a lack of knowledge as to how to effectively use it to achieve successful results and I just want to make sure that if someone is going to use that they know its limitations as well as benefits. I am constantly testing it with different types of materials and as I mentioned earlier, was successful this past week in sintering the new Art Clay Copper.


  1. Why do my pendants loose their shape while firing

  2. I am having problems using dichroic glass in my designs. I have a 1100 watt microwave. No matter how I adjust the power level and time my dichroic pieces dont fuse all the way or they melt into a blob and the dichroic pieces is malformed and sometimes burned out.