It is made from 85% Ferro Frit 3134, 7.5% kaolin and 7.5% silica. While not obvious from the recipe, one look at the chemistry of this (as displayed when you enter a recipe into your account at insight-live.com) will show very low Al2O3. Frit 3134 has almost no Al2O3, yet it is an essential component of functional glazes (for durability, resistance to crystallization, stability during firing). The kaolin is the only contributor of Al2O3 and there is only a little. A simple fix would be to use Ferro Frit 3124 instead, remove the silica and increase the kaolin to 15.
Five common North American Ferro Frits fired at 1850F on alumina tiles (each started as a 10 gram GBMF test ball and flattened during the firing). At this temperature, the differences in the degree of melting are more evident that at 1950F. The degree of melting corresponds mainly to the percentage of B2O3 present. However Frit 3134 is the runaway leader because it contains no Al2O3 to stabilize the melt. Frit 3110 is an exception, it has low boron but very high sodium.
|Materials||Ferro Frit 3110|
|Materials||Ferro Frit 3195|
|Materials||Ferro Frit 3249|
|Materials||Ferro Frit 3124|
|Materials||Ferro Frit 3134|
Glaze chemistry is the study of how the oxide chemistry of glazes relates to the way they fire. It accounts for color, surface, hardness, texturem, melting temperature, thermal expansion, etc.
Frits are used in ceramic glazes for a wide range of reasons. They are man-made materials of controlled chemistry with many advantages or raw materials.
Most ceramic glazes contain B2O3 as the main melter. This oxide is supplied by great variety of frits, thousands of which are available around the world.
|Glossary||Calculated Thermal Expansion
The thermal expansion of a glaze can be predicted (relatively) and adjusted using simple glaze chemistry. Body expansion cannot be calculated.
Understanding your transparent glaze and learning how to adjust its melt fluidity, thermal expansion, color response, etc is a base on which to build all your other glazes.
Shivering is a ceramic glaze defect that results in tiny flakes of glaze peeling off edges of ceramic ware. It happens because the thermal expansion of the body is too much higher than the glaze.
|Tests||Glaze Melt Fluidity - Ball Test|
|Articles||Where Do I Start?
Break your addiction to online recipes that don't work. Get control. Learn why glazes fire as they do. Why each material is used. Some chemistry. How to create perfect dipping and drying properties. Be empowered. Adjust recipes with issues rather than sta
|Recipes||G1916Q - Low Fire Frit 3195 Glossy Transparent
An expansion-adjustable cone 04-02 transparent glaze made using three common Ferro frits (low and high expansion) and a suspension strategy that produces an easy-to-use slurry.
|Temperatures||Common frits begin melting (1400F-)|
|Temperatures||Gerstley Borate Melts Suddenly (1600F-1650F)|
Ask the right questions to analyse the real cause of glaze shivering. Do not just treat the symptoms, the real cause is thermal expansion mismatch with the body.
|Oxides||B2O3 - Boric Oxide|