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Boxes are 20kg (22.68 lbs). Plus there are enough trimmings to make about two more. That is about 500g of pugged clay per mug. These have been trimmed and engobed (using our standard cone 6 engobe) and are drying. Notice I have waxed the outers of some of the handles to slow their drying down (to keep it in sync with the mug itself). M390 is likely the most plastic native Plainsman body. Although it was not overly soft I stiffened up the clay for ten minutes on a plaster bat to make it my ideal throwing stiffness.
Wowzers! These are actually hand-made, not thrown on the potter's wheel. You can see the vertical join by the handle as it rotates. Her's is a simple concept: A red clay (M390) with a thin application of partially opacified matte glaze. She flaunts a bare red clay base, polishing it. You can find her easily on Instagram and google.
This is a calcium matte base (as opposed to the magnesia matte G2934). The clay is Plainsman M390. 5% Zircopax was added on the left (normally 10% or more is needed to get full opacity, the partially opaque effect highlight contours well). 5% tin oxide was added to the one on the right (tin is a more effective, albeit expensive opacifier in oxidation). The PLC6DS firing schedule was used.
This mug was thrown. But the handle was cast from L4005D, the recommended recipe for an M390-compatible casting body. This is not a product you can buy, you have to mix it yourself, but we have plenty of instructions and pictures. The fired maturity of the two (fired shrinkage and porosity) matches very well. The casting process is superior for certain shapes and ware types. And now, with 3D printing, it is much easier to make many kinds of casting molds. This handle mold is made by pouring plaster into a 3D printed form. These are strong, the handle on this glazeless mug endured a couple of good taps with a hammer and stayed solid. With glaze, the strength would be much better. The body fires a little browner in color than M390. It would be redder if we included more iron oxide in the recipe, but that would gel the slurry and make it harder to work with. As a red-burning body, this one has better casting properties than any other we have used.