So far since the holidays, I’ve been busy testing new glazes for 2017. With one known glaze recipe, or inputting a known total flux amount using materials I have in the studio, you can easily come up with a 35 glaze grid using the Ian Currie method of volumetric blending.
To further explain, I will start with one initial recipe which was for a Chun Seafoam, with Cobalt Oxide replacing the copper carbonate called for in the recipe. I inputed the recipe, minus the clay and silica, into the database on the Ian Currie site (which gratefully his son is still maintaining since his father passed). The algorithm will come up with 4 glazes for you to mix, labeling them A,B,C and D.
You cannot be too organized in this process – it is not difficult to learn, but organization is a plus. I color coded each of the 4 glazes, as well as color coded and labeled each of the 35 clear plastic cups with their cup number as well as measurement proportion for each glaze. You will find the measurement proportions in Ian’s book.
The cups are laid out in 7 rows of 5 and are labeled 1 to 35, simulating the order of boxes within the grid. The mixed glazes, A, B, C and D, are then carefully measured into each corresponding cup using a 60mm syringe.
Once each of the 4 glazes are measured out correctly into each of the 35 cups, the glazes in the cups are blended thoroughly, then dispensed into each corresponding box on the grid. I mark the number one square in the upper left hand corner with a bit of red iron oxide. In the book, Ian Currie uses a syringe to do this, but I found the glaze to go all over with the wide opening of the syringe. I was much more successful squeezing the glaze into the grid spaces with a slip trailer. In the lower right hand corner of each box, I made a ‘T’ indicating a second coat thickness.
Based on the specified proportions of glaze A, B, C and D you dispense into each cup, the program automatically gives you the recipes for each of the 35 glazes in the grid. I found it helpful to print out, laminate and permanently adhere this information to the back of each corresponding tile grid. That way, all the visual, and printed information is in one location and easy to see at a glance. If I want to know what the recipe is for any of the 35 test glazes in the grid, it’s right on the back.
This is a very quick explanation of how this glaze method works – for a more in depth look and a full explanation on how the glaze proportions affect the amount of silica and alumina in the glaze providing an easy way to ‘read’ the grids, I would really recommend purchasing Ian’s book. It really does make the process simple and easy to comprehend.