|Monthly Tech-Tip |
Fusion Frit F-19 is claimed to be a substitute for Ferro Frit 3124. The glaze was applied on Plainsman L210 and fired at cone 04 (not as thick as would be customary on Majolica ware). Left is with Ferro Frit 3124, right is with the Fusion product.
The mug on the left has three coats of Spectrum Majolica base, painted on by brush. Drying was required after doing the inside coats, so the total glazing time was several hours. The glaze layer is way too thin and it is not even at all! The one on the right was dipped in a 5 gallon bucket-full of G3890 Arbuckle white (that was weighed out according to a recipe and slurried at 1.62 specific gravity). It took seconds to dip-apply, the thickness coverage is good. As is obvious, it makes sense to make your own base white. Then decorate using the overglaze colors (e.g. the Spectrum Majolica series). Another advantage of making your own white is that you can splurge on the amount of opacifier (in this case 9% zircon and 4% tin oxide), to achieve maximum whiteness and opacity. And, you can proportion a mix of two frits (having higher and lower thermal expansion) to fine-tune the fit with the body (a big issue at low fire).
Majolica is white opaque glazed red earthenware clay having colored overglaze decoration. But if you know more about what it is technically you will have more control of your product.
Material substitutions in ceramic glaze and body recipes must consider their chemistry, mineralogy and physical properties
Fusion Frit F-19