Monday, November 28, 2011

Nerikomi and Firing Temps


For the nerikomi platter pictured above I brushed different glazes on the flowers, stems, and leaves. The background has another glaze brushed on. The background glaze reacted with the minerals in the red clay and essentially is a neutral color but still appealing against the color of the flowers. This piece has me thinking about geometric shapes for a tile wall hanging and I'd like to try inlaid clay on a vertical surface. Every piece I make elicits exponential numbers of ideas.

This platter is a continuation of my ongoing experiments with nerikomi or inlaid clay. Years ago I made several plates with inlaid clay which were fired to Cone 10. Now that I'm working at Cone 6, I decided to do some tests several months ago where I inlaid circles of white stoneware into red stoneware clay. My miniature test bowls cracked after the glaze firing and the inlaid clay was beginning to jut out of the red clay. I also made a window with a red clay frame and white clay curtains and the red clay shrank and cracked the white curtains. The shrinkage rates for both clays were the same at 11 percent so I wondered why that happened.


After looking at the cones of the previous firing, cone 5 on left and cone 6 on right, I decided the kiln fired at too high a temperature the last time. Cone 6 is melted over.


I decided to reduce the hold time and raise the bottom cool down temperature by 100 degrees. From the left Cone 4, then 5, and 6. The platter fired without the previous problems of cracking and pushing the embedded white clay up. If you recall the glaze on the tin cup from this firing was shiny. With a longer hold time the glaze would be more matt. In the future I will have to fire the work according to how I want the glazes to turn out, some with less hold time and some with more.


For the bisque I used the cone fire program of 04 already in the kiln and cone 05 and 04 are melted over. I think my kiln fires hotter than the program says. I'll check the manual to see if I can adjust the programs to match the cones. How long do pyrometers last? Or how many firings should they last?


For this 10 inch bowl I impressed leaves into the wet clay. After bisque firing I hand brushed different glazes on the leaves and on the background and I used a different glaze on the rim and underside. I used the same color background glaze on this bowl as the platter above and it's essentially the same color as the clay but with a nice sheen. It has an earthy look which I find appealing. There are a couple of spots where the background glaze turned a darker burgundy color.



This textured platter came out nice because the red color of the clay shows through the texture giving it an antique look. More results from this firing tomorrow, so stay tuned. Thanks for all of your comments and suggestions, I really appreciate your input.

8 comments:

  1. Love the look you are getting from the red clay. That first platter is really beautiful.

    ReplyDelete
  2. Hi Patti, thanks so much. The red clay reminds me of earthenware even though this is stoneware, it has a red terra cotta color to it though which I like. I hope to make more of these.

    ReplyDelete
  3. When I first saw your work I thought you were using terra cotta. Like the way your glazes work with the clay body. That last platter is a keeper.

    ReplyDelete
  4. Beautiful, I want to try that clay. What a great find.
    The platter is beautiful, nice job.

    ReplyDelete
  5. Hi Smartcat, thanks, this clay is called terra cotta, but it isn't a terra cotta clay if you know what I mean, it's a cone 6 clay with a red color.

    Hi Lori, thanks, the only thing with this clay is it has a lot of grog in it and if I work it too much the grog comes to the surface which can be a problem when smoothing the edges of bowls and such. I have been using this clay since I moved to Florida, but this is the first time I used these particular glazes of this clay body which gave the rich background color, shoot me an email if you want to know the particulars on the clay and glazes and I'll look up the details.

    ReplyDelete
  6. The pressed leaves in the wet clay...magnificent.

    I read: firing temps.. & thought of firing temp employees..opps.

    ReplyDelete
  7. Love this look... The first one is my favorite, but they're all pretty darn cool.

    ReplyDelete
  8. Hi Mary, thanks, funny how words mean different things. no firings here and no hirings either. Ha!

    Hi Turquoisemoon, thanks so much. the dark clay gives a nice contrast. I got your email and will be mailing very soon.

    ReplyDelete

I love suggestions, questions, critiques, thanks for your comment