For the previous post on this clay https://daylenes.com/2021/07/27/test-the-sandstone-clay/
I tested each batch only once. For better accuracy, do multiple tests. However, this tells me that I need to add more Neph Sye than I like. The sodium in Neph Sye is partly soluble, leading to thixotropy issues in clay bodes if used in large amounts. I don’t use more than 12%. Since this clay is already slightly thixotropic, the 15% I would need to add to get a good cone 6 clay body, is less than ideal. Additional tests are being performed. You can read about them here. https://daylenes.com/2021/08/12/more-testing-on-the-sandstone-clay/
Added Nepheline syenite | Fired Shrinkage | Fired Porosity |
8% | 11% | 5.8% |
10% | 11% | 5.1% |
12% | 10% | 4.8% |
14% | 12% | 2.2% |