F CLAY Q
Most of our clay bodies have a RANGE of water for its recipe. We mix multiple batches of each body at a time and we vary the water from the first to the last batch. The batches mixed with more water are ideal for us to store for aging and selling to distributors after several months. The stiffer batches are ideal for filling more immediate orders. Some times of the year, it is hard for the production cycle to keep up with the demand and the speed at which clay leaves our warehouse. Years of planning and refining those plans help to guide our production for back to school, which we begin in February. Our targets are routinely evaluated and updated for the changing market and the needs and preferences of our distributors and end users. Despite all of this, every individual has their own preferences based on their methods, techniques and style. The great thing about clay is that it is highly customizable for individual purposes:
If your clay is too stiff for your purposes, you can open the bag and pour in one quarter cup of water, then seal the bag up. Over the next 24-48 hours, that water will absorb into the clay and soften it. You may want or need to invert or rotate the bag during this time period for faster and more even absorption of the water into the clay.
If your clay is too soft for your purposes, open the bag and pull it halfway down the pug of clay and let it sit in the open air for 2-6 hours (depending on the time of year and humidity in your location/studio)
Pudding/ “Slop in a bag”
If your clay is so soft it will not hold its shape, then it froze at some point. We do not mix clay that soft, ever. The clay is pushed through a large extruder in blocks that are cut and bagged. Clay that is described as pudding or slop in a bag simply can not come out of our machine like that. This is always the result of clay that has frozen and thawed. It is still very usable and the freeze/thaw actually makes it far more plastic and wonderful to work with, but it does require wedging. You should find that after a small amount of wedging on a canvas-covered wedging table (or you can use the throw-it-on-concrete method of wedging) that the excess water from the freezing will realign with the clay platelets and your clay will be 100% workable and usable.
If your pot is breaking apart in your hands after firing, then you are experiencing dunting. Dunting is almost always the result of heating or cooling too fast, and is most commonly noticed in single-firing applications, but it can also happen in electric kiln firing with a separate bisque and glaze firing. Some clays are more susceptible to dunting when these conditions occur while others are more resilient. The digital fire database has a lot of good information on dunting which you can read here: https://digitalfire.com/glossary/dunting
Dunting is not considered a defect of the clay, rather a mismatch between the choice of clay and firing or glazing techniques. If you are experiencing dunting with the clay you have selected and want to continue using that clay because you really like it, you should look at adjusting your firing style/schedule and/or glaze selection/application. If you like your firing and glazes, you might consider selecting a different clay body.
popouts or “junk” in the clay
This is caused by contamination in the clay. This could be (and is most commonly) foreign materials from the mine that somehow did not get screened out during packaging. It could also be contamination introduced during the mixing and packaging process or it could be contaminants from the end user’s studio space. At our facility, we take great care to ensure nothing goes into our mixer other than the material in the bags plus the water, but we don’t claim to be perfect. If you find something unexpected in your clay, whether during the construction process or post firing, please do let us know using our Feedback Form. We will investigate and if we find that the junk was our fault, we will replace your clay.
If your glaze is flaking off of your pot after the glaze firing, you are experiencing shivering. This is caused by an incompatability between the clay body and the glaze. If you are making your own glazes, there are modifications you can make to the glaze to provide a better fit with your clay. If you are using commercial glazes, the best solution in this situation is to either select a different clay body or a different glaze. If you want to learn more about shivering, check out the digital fire database article on it: https://digitalfire.com/glossary/shivering
These tiny cracks in the surface of your glaze are usually the result of poor glaze fit, in which the clay is shrinking more than the glaze. Digital fire has excellent information on crazing causes and solutions: https://digitalfire.com/glossary/crazing
Mold on the Clay
Much like in cheesemaking, mold on clay is a GREAT thing! This means that it has aged well and the more aged clay is the more plastic it is. Typically mold will be found on porcelain clays, but it can also appear on stoneware clay. Mold on clay is NOT harmful to your skin in any way. If it bothers you, feel free to slice the mold off and pitch it into your slop bucket. It will disintegrate there and just improve your reclaim!