Hi All I just began slip casting block forms from stoneware slip and it has been going well for my first time. I’m having the problem that while they are drying, the edges are warping and no longer staying square.  I left them to dry in the mould for 4 hours before demolding as I thought there may be thicker clay on the edge below, so the walls are ‘sinking’ as it dries.    I am using both red and white slip, and it happens a lot more with the red. Does anyone have any ideas? Shoul