Kiln Firing 1/24/10

This was the wettest kiln firing to date. Not sprinkling but pouring! The rain wasn't evaporating fast enough off the hot kiln so I had to rig up an umbrella. It worked pretty good. And, unlike the previous firing I didn't have any casualties.

I was a little nervous but because when I loaded the kiln I broke my own rule and instead of 4 inches at the top of the kiln I only left 2. Normally, not leaving enough space for air flow is a good way to get your art blown up, but I was hoping that I would have enough air flow between my pottery on the top shelf (shown in the picture below) because of how I stacked it. The air flowed nicely through the plus shape (or x shape) made from the empty space between the pots.
The top shelf ended up a little cooler that the bottom shelf. I could tell this by the pyrometric cones. The cones on the top shelf were just barley melted over where as the cones on the bottom shelf were almost starting to pool up. The picture below gives you a better view of the cones.

Here is a picture of how the bottom shelf was stacked. All I had room for was the big pumpkin.


And now here is a picture of the bottom shelf's cones.


I think next time I might slow down the firing for the last few hours so that the kiln will come to temperature a little slower and more even. Some of my earlier firings have turned out a more even than any of the firings I have blogged about. Lately I have been speeding up the process a bit. Maybe I should slow back down. Here is the kiln data sheet.

Another problem I have been having is that near the end of the firing my 9 gallon propane tank looses pressure and I have to shake it to keep the propane coming out strong. I might need to get a propane take that is just a little bigger. All in all it was good firing. It came out fairly even and I'm happy because my pots are bisqued and I didn't have anything explode.