Tuesday, December 25, 2012

Glaze testing

The availability of hundreds of glaze recipes and information is readily at your fingertips with computers and the many publications available today.  Over the years my file folders have grown to several full folders of recipes and with the onset of glaze programs, that folder has burst into a well organized unit that helps eliminate duplicates and understand glazes.  But with this great technology, all this does not tell you which glazes will work best in your kiln and its atmosphere, and with your firing methods.
Many of the books available have examples of line blending and triaxial blending which work well when you have found that one glaze that has possibilities.  I wanted to size down the vast amount of formulas and yet cover several varieties of glazes.
I started my search for glazes in the periodical section of the school library and found most of the glazes I have used over the years.   To help find those glazes that would work for me I just took a piece of paper and drew rows and columns of lines, using the rows across the top of the sheet for the code of a particular glaze (ie: Temple white becomes TW01, TW02, etc., or if you have Tashiko White, it becomes TaW01/TaW02).   The columns along the left side becomes the ingredients used by each glaze in the row at the top.  The problem is that I kept lossing the booklets or having to look through ten or twenty different books to find my test.
Note:  I now label each glaze in my data base (I use Hyperglaze) with its code directly after the name of the glaze.  Keeping all this in one place is very important and saves repeating steps.
I like to work with about 10 glazes on each testing.  I set a template up in a database and save it for use later to use on a new set of test.
Each series of test lets me take certain types of glazes, feldsparic, barium, or other base types and keep the amount of ingredients to ten or less.  I set up 10 cups marked with the code of the glazes and enter the formula in the column under each glaze.  (I like to use a 300 gram sample for all the test). 
I find it much easier to take down the feldspar jar one time, which usually would be the first ingredient in that column and measure out each amount of feldspar for each glaze and place it in the cup.  I then can go on to the next row in the ingredient column.

                            TW01     TW02   TaW01  MR01    RY01


I hope this simple arrangement will work for you and if you got a good ideal pass it on, I'm always open to making this easier.
Merry Christmas to all and a happy New Year