Wednesday, July 30, 2008

New raku glaze via class

I was in the second session of the glaze class I am taking last night. One of the exercises we did was to make a raku glaze without a recipe and we had to measure it by parts not by weight. The only help we got with the recipe was a reminder of Soldner's base recipe of 80/20 grestely borate/neph syn.

This was a lot of fun for me. We we just firing and NOT reducing the test tiles so nobody was adding coloring oxides. It was really just make up a glaze and see whatcha get.

I know that lithium can be a valuable addition to raku glazes. I use a couple recipes with 20% + lithium. So that's where I started; 2 parts lithium. For my unit of measure I used a plastic spoon. Next I wanted to keep the recipe total at 100 parts. Well, really I did 10 parts not 100 but it's easy to expand to 100 from 10. Knowing the lithium would flux the bejeezus out of the glaze I cut back on the grestely; 3 parts grestely. Lastly I rounded it out with neph. syn. Neph syn while in most glazes is a flux at raku temps is really a stiffener; 5 parts neph syn.

Lithium 2 parts
Grestely Borate 3 parts
Neph. Syn. 5 parts

Now this is different than how I normally do glazes because I have no idea what the weights are. This does NOT translate to grams or ounces. I will probably go through and reproduce this and figure out the weights of this recipe.

The results were really nice. Very crazed, very bright clear. Melted completely yet did not run. It produced a subtle greenish pink tinge and a halo at the glazes edge.

I am going to try this glaze soon. I will try adding iron (for oranges) and copper because hey we're talking about raku.

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