Why do we want to use a clay body that has lots of grog in it for raku firing?
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Why do we want to use a clay body that has lots of grog in it for raku firing?
Grogged stoneware clay is suitable for raku firing. Grog helps make the pottery more resistant to thermal shock and reduces shrinkage.
Can you throw clay with grog?
Grogged clay is also good for firing, as it is better for expanding and contracting without cracking. Grog can also add a brilliant texture to your pottery and ceramic pieces. The temperature in which you fire your grogged clay should also be a consideration, as grogged clay can often fire quite a lot quicker.
What do you add to clay to make it stronger?
Apply Paint or Sealant. A coat of acrylic paint, sealant, varnish, or lacquer makes the air modeling clay craft stronger. You can apply several coats but make sure that the previous layer dried completely.
What does Molochite do to clay?
Molochite 120 is a 120-mesh grog that is great for use in porcelain clay bodies, as it is the cleanest, whitest grog available. This material is made of calcined Grolleg porcelain, and is typically used in the whitest porcelain clay bodies to reduce cracking in drying and firing.
How much grog do I add to clay?
A sculpture clay body, for example, typically has 15-25\% grog (but can have much more). Since grog is typically prefired, its does not normally undergo a firing shrinkage (unless the body in which it is a part is fired to a temperature higher than the grog was initially fired at).
What can I use as grog in clay?
This is because the iron affects the white color of the porcelain. However, a substance called Molochite can be used as grog in porcelain. Molochite is made of kaolin, a white clay, that has been fired at a high temperature. It is a clean grog with a fine mesh of 120.
What can be used as grog?
However, a substance called Molochite can be used as grog in porcelain. Molochite is made of kaolin, a white clay, that has been fired at a high temperature. It is a clean grog with a fine mesh of 120. Also, it is glassy and white when fired, so it does not compromise the texture of porcelain.
Can I use sand as grog?
Sand has the same forming properties of grog in the greenware stage. But since it’s essentially ground up silica, an ingredient in clay and glaze, adding too much can cause fit uses between the clay body and glaze. Experiment with ratios of sand to clay. Less than 7\% sand to clay is a good rule of thumb.
How much grog do you add to clay?
Can you use sand as grog?
Sand has the same forming properties of grog in the greenware stage. But since it’s essentially ground up silica, an ingredient in clay and glaze, adding too much can cause fit uses between the clay body and glaze. Less than 7\% sand to clay is a good rule of thumb.
What can I use for grog?
What is the purpose of grog?
Grog is used in pottery and sculpture to add a gritty, rustic texture called “tooth”; it reduces shrinkage and aids even drying. This prevents defects such as cracking, crows feet patterning, and lamination. The coarse particles open the green clay body to allow gases to escape.