Saturday, July 4, 2009

Good news bad news

Well, good news is, my kiln is pretty easy to fire and I think I like it. Bad news is being impatient does not pay off. The firing results are abysmal. I got up this morning and the kiln was at 200 degrees so I peeked in. All bad, so I went back to bed until I could face it without taking everything out and smashing it on the concrete the kiln sits on. My first thoughts are why the hell am I doing this in the first place. Maybe I should just stick to Raku, I am always disappointed with cone 9 functional stuff I fire. Never disappointed with my Raku. Then I just started to work out in my head what went wrong and what do I do about it. The pieces are worth trying to salvage if I can. There was no reduction at all, glazes didn't melt, so I didn't get up to temp, so I think I can refire. I should have reduced longer, I wasn't really sure how to do it with this kiln, gotta figure that out. Can I put it all back in and fast fire back up to temp? What is the best way to do this? And I think I should have soaked longer at the end. I did get a blue test that I like a lot and the ash has possibilities but my application was over the top. The once fired pieces survived but the ash glaze is crazy on them and very blistered. I went back and read Brandon's blog and Meredith's for moral support. They both have had some ups and downs with kilns this month and it helped reading their posts again. And of course Andrew's spirited approach helps a lot. His blog gives me a lot of motivation to try things I might not try normally. Honestly the first thing I wanted to do this morning was to get on the blog and hear from all of you out there. You know what I'm going through better than anyone and there are years of wisdom out there that can give me good advise right now. I'll put some photos up later, but right now I'm getting ready for the Tour de France and making breakfast burritos to celebrate the start of our favorite sporting event of the year. It's all lessons, isn't it?


Ron said...

Hey, Sorry that firing didn't go very well. It's rare you get a good first one, but it is good news that the kiln fired well. Were some of these glazes you had used before? I mean you know some of them work right? I don't know if refiring would be worth it, not the whole kiln load anyhow. Maybe just pop a few in the next load. I'd put cones throughout so you can see what's happening temp wise. I think I would always go into body reduction around cone 08 for 30 and then just continue firing in light reduction for the remainder of the firing. I'm sure Brandon or Meredith will have better info. It's been awhile since I've had a glaze reduction kiln. Still, keep at it. The next one will be better.
Have a good 4th and enjoy the Tour.

Linda Starr said...

I can't believe I missed so many posts on your blog. All your work looks so great and that green flower pot is beautiful. Can't wait to see your log tray. That slug color would be a beautiful glaze wouldn't it?

Sorry about the firing, as you know I have been there too many times myself, but some of my refires did wonders, so it's definitely worth a try for sure. For the kiln at the college I found one firing one glaze would come out spectacular and another not so; then the next visa versa, all depending upon how the firing went. Then a few glazes always came out (if not underfired)- celadons, blue flambe, teadust and tenmoku. Is your kiln run on gas? I am curious, why cone 9 rather than 10? Looking forward to seeing photos of your results and to find out about your once fired pieces - which I would also like to try. Happy 4th to you and your family.

Alex Matisse said...

Tracey...Im sorry to hear about the frustrating firing. I think one thing to remember is that just because you have the temperature on the pyrometer that signifies the temperature when a cone melts it still takes time for that cone to melt and the glazes to mature at the that temperature. My guess is the kiln was hot but was not hot enough for long enough. As the reduction Ron's advice sounds good. In actuality I know very little about glaze chemistry and even less about firing gas kilns. I have not done it since college and even then it was just a handful of times. Next time pop some cones in there. I think that you could refire and get the glazes to melt properly but it would not help your lack of reduction. I could be wrong there too but someone else with more knowledge than I will have to chime in. Good luck!

tsbroome said...

Hey Guys: Thanks so much for the comments. Rob, yes I have used the glazes a lot, in fact chose these because they are consistent and I know what they do. I did a body reduction at 06 for 30 minutes and then again at 9 but I think that I didn't hold it long enough at 9 and I didn't soak long enough because there were some pinholes in the ash glaze.Linda, the glazes I used are from Claymakers and we go to cone 9 with them plus I wanted to make sure the temp under my shed was ok at 9 before I went any higher.I thikn I want to go to 10 for sure next time. The shed seemed to be ok with the heat. I did put up some backer board over the kiln to help protect the wood. I also thought the slug would be a great glaze. Alex, thanks for the input, I do think that the biggest problem was not using cones, and I knew this when I started, just too far along by the time I realized I forgot them to do anything about it. I'm still trying to figure out how you would see them with this kiln because the peeps are really small, don't know why, I may call Olympic about that. All in all, I think about half of the load can be saved by refiring and the other half was stuff with mediocre handles or bowls with sketchy interiors, so I didn't mind too much losing any of it. I learned a lot which was sort of the point in this firing. Plus It was only about half full, so I didn't lose a great deal. I really appreciate your comments especially on a fun holiday, so thank you a bunch,all of you!!