Tuesday, December 20, 2011

The Good, the Bad and the Ugly - Carbon Trap Shino

It's been a great year - with lots of gas firings and three wood firings as well as my workshops at MISSA.  I have been really interested in the carbon trapping shinos and have been using Malcolm Davis's recipe. I was very sad to learn of his recent death. I have read the presentation that he made at NCECA last year and what a wonderful career he had! Someone who we can really admire. If you want to read it - here is the link:
http://www.nceca.net/static/documents/MalcolmDavis.pdf  It's too bad that the slides that he used in the presentation are not available as well.
So here are some pictures of my Malcolm Davis Shinos - with and without Red Art. The one with Red Art is used on porcelain - with no Red Art you do not seem to get the orange colours on porcelain.
The Good: MD Shino without Red Art - Dan Hill's lithium slip with cobalt was first sprayed and then wiped off the the trees. Then sprayed with MD Shino without Red Art. Then the trees were waxed. The carbon trapping at the edges of the tree trunks is really great. I've been trying to replicate but so far with no success! Fired to probably cone 12 - 13 in my June 2011 firing.
Since I use  both B-mix - a porcelaneous stoneware and B-Mix for Wood Fire ( I presume it has something added to aid flashing) I tried both MD Shino with and without Red Art as I was not sure which one to use. In the gas kiln there seemed to be little difference between the two types on the above clays. However in the wood kiln the MD without Red Art seemed to get very little orange colour and the one with, seemed to go rather dark, more brown than orange. Maybe the ashes are washing out some of the orange?  So not sure which MD Shino to use from now on.

The Good: DH lithium slip sprayed on right and bottom as well as rim of bottle. Sprayed with Wirtz Shino  and then poured on  MD Shino on right shoulder. You can see how the lithium slips tends to bubble through. Same firing as above - in fact pots were next to each other. There was great carbon trapping where the shino was thicker due to the poured layer on the shoulder. Unfortunately this pot cracked on the bottom seam.

The Good: Dark stoneware clay - one half poured with MD Shino with Red Art on left and the other half without Red Art. Waxed out design. Got great carbon trapping but no orange hues.

The Bad: Used again Dan Hill's lithium slip with cobalt and then sprayed with MD Shino without Red Art. Sprayed a light coat of MD with Red Art over the upper area of the trees and people. Appliqued areas then waxed. You can see that it went orange there, but the bottom part was totally white - totally oxidation I guess. My end of Oct firing. The colours are not bad - but not what I was looking for in a Shino.

The Ugly: MD Shino without Red Art - and without any lithium slip. Appliques were waxed out. Really ended up washed out. The ash deposit on the left removed what little orange blush that there was. I have to remember to take that into consideration when I load the kiln and make sure that the ash works with the design and not against it.

The Ugly: Lithium slip on top part and then wiped off the appliqued areas. Sprayed with MD Shino with Red Art - plate cracked but you can see that the orange on the left is not a vibrant colour. On the right there is quite a bit of ash deposit. Again the trees were waxed out, but no carbon trapping either.

1 comment:

  1. I share a Propane fired saltglazing kiln, we haven't been firing regularly-about six times a year if we are lucky...We get more carbon trapping when the weather is wet and windy. It seems unpredictable!