Friday, August 20, 2010

Burning Kiln Time

No, I'm not going to set my kiln on fire.
I don't think it's even a combustible.
This morning was one of those mornings when things can either be really good or really bad.
Well, not really really bad, but still it could have been bad.
I fired the Industrial Teapot last night so when I woke up I couldn't wait to see how it turned out.
I fired the two cups separately, so there that was an issue. Sometimes when you fire stuff at different times, you get different results; not so much with my firing how as it's all done in oxidation.
I also discovered that one of the glazes I used needed to be fired two cones hotter, which means the glaze probably was not fully maturing.
The thing is, it's too late to do anything about it since there are three glazes on the pieces and refiring to a hotter cone would over fire the other two glazes.
Still, the results were acceptable.
Sort of.
Here's the trio:

The glazes I used were metallic, not lustres, we'll get into that later, but a glaze that if I had to guess looks like they are overcharged with metallic oxides like chrome, iron, manganese and cobalt.
How do I know this?
Well, I formulated a high fire glaze using these components and got similar results.
Now the bad.
The lid doesn't match the body:

This looks like it's due to glaze thickness. I needed to give the lid one more coat to get it to match. This sometimes happens when you are glazing separate pieces.
I don't like brush strokes:

Or inconsistencies in the glaze surface for that matter. Sometimes it can't be helped. The glaze on the "band" is the glaze that's supposed to go hotter so, I don't think that can be helped.
There isn't as much contrast between the bands and the body as I wanted. Again, probably due to the fact that the bands are unfired, there's not much I can do there.
I'm not real happy with the look of the handles:

I knew I wanted the handles to be different, just not this different. I could have used another glaze and taken it in a different direction, but I wanted to stay in the same color spectrum. I glazed the cups first so I knew of this, but since the cups were already done, I sort of had to follow the pattern.
The lid will be refired.
I'll give it another coat of glaze and see if I can get it to even out with the rest of the pot.
I'm still debating on whether or not to refire the whole thing. Of particular interest are those handles.
I may just take some wet sandpaper to them to dull the gloss down and give it satin finish.
On the other hand, what I got may just grow on me.
I'll wait for later in the day when the light changes.
Okay, there you go, funky teapot from start to finish.
Well, not quite finished for there is one more detail to do.
I didn't get to do the Unidentified Flying Teapot for I forgot to pick up the patching stuff at the ceramic place yesterday so I couldn't do the body work.
I'll get that done tomorrow and I'll be sure to take more care when glazing it up.
I don't like to refire things.
First it means I didn't do it right the first time, and second, it seems like an awful waste of kiln time and space.
Well, it's my personal kiln now so I suppose that doesn't matter.
Still, it's a waste of electricity.


limom said...

Coming from you I appreciate that!
I could live with them if the things I talked about weren't as pronounced. At least to my eye(which is not always good!).
After I got back from my ride, I put another coat of glaze on them and put them back in the kiln.
Hopefully, this will get the job done.

nedis said...


i was just seeking a glaze with that silvery look.

would you share the glaze composition you tried?

limom said...

I think it was a Duncan low fire glaze, antique pewter.