Monthly Tech-Tip | No tracking! No ads! |
Dipping glazes can, in very controlled circumstances, be multi-layered. If you have done it for some time, with success, you may have been just lucky. These pieces demonstrate one of many factors that can produce failure: The top glaze contains 7% bentonite and 5% zinc oxide - that is 12% hyper-fine particles, perfect to create the drying shrinkage to make this happen. The recipe author must have reasoned that it could "pinch hit" for the inadequate clay content. But 7% bentonite in any glaze is highly unusual. And, it is actually not even necessary here. Why? The high percentage of Ferro Frit 3124 is sourcing needless Al2O3 (alumina), that should be coming from kaolin or ball clay instead. Frit 3134 is the perfect stand-in, it contains almost no Al2O3, but otherwise is quite similar. The equivalent recipe we calculated on the right has the same chemistry, but does pass a sanity check. It is not guaranteed to work, but has a better chance than this one. For assurance of success, the base should be mixed as a base-coat dipping glaze.
Media |
Substitute Ferro Frit 3134 For Another Frit
I use my Insight-live account to do the glaze chemistry to replace Ferro frit 3134 with combinations of three other common Ferro frits. We will see the challenges of doing this in three different types of recipes. |
---|---|
Typecodes |
Glaze Chemistry
Case studies where glaze chemistry was used to solve a problem. |
Glossary |
Glaze Layering
In hobby ceramics and pottery it is common to layer glazes for visual effects. Using brush-on glazes it is easy. But how to do it with dipping glazes? Or apply brush-ons on to dipped base coats? |
Buy me a coffee and we can talk