Last week I made some boxes that I will use when I am making plaster moulds for my slip casting. They are movable which means I can make a wide range of different sizes. They are going to be much more easy to use that the old system I was using! I simply used old boards of wood that I cut the same size and some small metal brackets I folded and screwed onto the wooden boards. Easy! This way I can slide them to change the size.