Consistency of Clay, Part 2
I'm going to continue the first blog I wrote back in April about clay. Recently something happened at HPG that I thought I'd mention here because it might be helpful. One of the potters was having trouble centering her clay and mentioned it to me. She asked if I would watch what she was doing and tell her if I saw anything that she was doing wrong. I watched for a minute or so and made a few comments. She began trying to do what I suggested but complained that she didn't have the strength to do it. So I asked if I could sit down at her wheel and she could watch me center the clay while I explained what I was doing. She agreed and I sat down at her wheel and put my hands on the clay. It was hard, really hard. I could barely budge it myself. I sat back and asked her what kind of clay it was. It was Soldate 60, but she had been throwing this same piece of clay over and over again. Another lady had been listening in and she said she was having the same problem with her clay. When I went over, her Rod's Bod was also hard as a rock and almost impossible to move. It made me realize that many beginning students like these two may have trouble throwing successfully because the consistency of their clay is unsuitable for throwing. Not even a virtuoso thrower would have success with it. When we throw a piece of clay like Soldate or Rod's Bod over and over again, the water we use washes away more and more of the very fine clay particles but leaves behind more of the coarse grog or sand. After using it several times, the increasingly higher proportion of grog or sand makes it too stiff for further use. It should be mixed back into a much larger piece of new clay or recycled. So check the consistency of your clay and make sure you don't try to throw a piece that's not ready for throwing. If you try to throw clay that's either too hard or too soft or has some other issue, you'll have far more difficulty than you should at successfully completing a pot.
I hope this blog will be encouraging to potters, especially beginning potters, and a source of helpful information and comment.