These GLFL tests and GBMF tests for melt-flow compare 6 unconventionally fluxed glazes with a traditional cone 6 moderately boron fluxed (+soda/calcia/magnesia) base (far left Plainsman G2926B). The objective is to achieve higher melt fluidity for a more brilliant surface and for more reactive response with colorant and variegator additions (with awareness of downsides of this). Classified by most active fluxes they are:
G3814 - Moderate zinc, no boron
G2938 - High-soda+lithia+strontium
G3808 - High boron+soda (Gerstley Borate based)
G3808A - 3808 chemistry sourced from frits
G3813 - Boron+zinc+lithia
G3806B - Soda+zinc+strontium+boron (mixed oxide effect)
This series of tests was done to choose a recipe, that while more fluid, will have a minimum of the problems associated with such (e.g. crazing, blistering, excessive running, susceptibility to leaching). As a final step the recipe will be adjusted as needed. We eventually chose G3806B and further modified it to reduce the thermal expansion.
Pages that reference this post in the Digitalfire Reference Database:
Li2O, B2O3, ZnO, G2926B - Cone 6 Whiteware/Porcelain Transparent Base Glaze, Where Do I Start?, G3806C - Cone 6 Clear Fluid-Melt Clear Base Glaze, Fluid Melt Cone 6 Glaze Project Recipes, Transparent Glazes, Base Glaze, Borate, Reactive Glazes
This post is one of thousands found in the Digitalfire Reference Database. Most are part of a timeline maintained by Tony Hansen. You can search that timeline on the home page of digitalfire.com.