Many ceramic artists stress the importance of having glazes mixed to a consistent thickness especially when making incised ware. The purchase of a hydrometer can make all the difference in the world when mixing glazes. In this week’s Quick Tip, potter Mea Rhee of Silver Spring, Maryland, tells us how to make a homemade, low-tech hydrometer for the clay studio. Whether you go high-tech or low-tech, a hydrometer can help you achieve consistent results when glazing! – Jennifer Poellot Harnetty, editor.
You can make an inexpensive hydrometer out of a narrow plastic bottle, which can be found in the travel section of a drugstore. Start with the tallest, skinniest bottle you can find. Fill the bottom with about 150 grams of nails. Close the bottle and carefully float it into a well-stirred bucket of glaze. Add or subtract nails until the bottle floats upright, about three-quarters submerged. Now, when you have a batch of glaze at a consistency you like, carefully float the bottle into the glaze, and mark precisely the depth to which it sinks. You can then use this mark to check or repeat the glaze’s consistency whenever you like.