Sunday, July 3, 2011

Work in progress

July already, where do the months go? It's close to the middle of winter and Dunedin is yet to see a decent frost. This would be the first year the lawns didn't stop growing, maybe due to the Chilean volcano or a nuclear winter, but it sure makes for some great potting weather! Here are some pics of work in progress.                  
Some miniatures and some scaled up pieces with lids. As they get bigger I may have to add  handles and lugs.

Yesterday I added a work bench and more robust shelving. This small room off the throwing area is where I wedge, store and recycle clay, place pots on the shelves to dry and have a bucket of creek water to wash up in.


Here are a few test glazes from the previous firing using sump oil as a fuel. This is Marcus O'Mahonys " Light orange slip" The recipe is:  Porcelain clay (dry weight) 20 ( I used the white stoneware clay body) China clay 10, and Tin oxide 3. All recipes on this post are found on pages 232 and 233 in Phil Rogers book:  "Salt Glazing".

Here is the same glaze but on a buff stoneware clay body (southstone) All tests were dipped at least twice to get variations in glaze thickness. Note the interesting pattern around the top of this example where the glaze was quite thick.

A very typical salt glaze effect. This mottled texture is called "orange peel" and consists of an extremely simple glaze of just two components: Ball clay 50 and China clay 50, fired to 1300+  with plenty of salt.

In this example of Arther and Carol Rossers' "Blue slip" consists of : Feldspar 15 (Indian ), Silica 8, BBR (clay ceram)?? 30.5 (I used Kingwhite kaolin), Eucalyptus ash 15.5 (washed pine ash), Titanium dioxide 0.5, Cobalt Carbonate 1.  Now that I look at this recipe it doesn't resemble the original much at all. Part of the joy of pottery is the unexpected.

Another A+C Rosser Glaze "Green slip to be sprayed over blue" However,  this example shows only the green slip - a very beautiful glaze on its own.  I still have the test pottle, so in the next firing I'll try it over the blue slip above.
 In my next firing,  I will be using bigger batches of glaze on larger pots and firing a slightly bigger kiln.  I'll be using canola oil from the fish and chip shop, and comparing this to sump oil -  hopefully getting similar results.  

1 comment:

ang walford said...

some very nice results.. brilliant.. I love it that you're using oil from the chippy!!!