"the artist has one function--to affirm and glorify life."
- w. edward brown

Monday, November 28, 2005

Kiln fun

Well, It's late and I'm alone in the art basement... and the kiln is still on and getting hotter, which is good.

I've turned up the heat on it, actually turned the pressure up, allowing more gas to get to the burners, making it get hotter, and I have closed the flue a little bit, so that the reduction starts. What that means is that the gas dosen't all burn in the kiln because I'm reducing the amount of oxygen that is able to enter the kiln, and because of that, the gas has to get the oxygen from somewere to combust, so it begins to take it from the compounds in the glazes and in the cly body, causing different compounds to form than would in a oxidation firing, where the oxygen is left free...

needless to say, its pretty complicated chemistry that's happening... but its really cool to understand the reactions and stuff...

So while I sit and monitor the kiln and make sure everything is staying where it should, as it tends o fluctuate a little at this stage, I am getting some homework done. Lots of fun stuff happening... I'l be sure to let you all know how it goes. hopefully there will be some good pieces in this firing!

4 comments:

Katie said...

So when you change the pressure, is that what causes some of the stuff to break? What do you call this firing, if the other is "oxydation?"

MLE said...

Wow. You started off slow on this whole blogging thing, but you're sure loquatious now! Thanks for all the updates. Too bad you missed "Harry Potter" with us, but glad things are under control now.

Katie said...

Haha - Bob IS the "Hairy Potter!"

bob said...

Katie, this type of firing is called a 'reduction' firing, because you reduce the amount of oxygen in the kiln, and to keep burning the fire takes oxygen out of the chemical compounds...
Here's an example, in an oxidation firing, Copper Oxide will most often be a green color, due to the oxidatation of the copper metal. In a reduction firing, depending on the glaze, the copper can turn the glaze to a red... and the more reducing you do, the more red the glaze turns out... mom has a jar at home that I can show you when we get home and explain with... :)