Well, the step by step mould is coming together. Three pieces cast in two hours at college. Now working on plaster with special additives of pva glue and de-ionised water, both of which come heavily Interweb and recommended. The latter also has various scientific papers backing up its use, such as the snappily titled "Effects of preparation variables of plaster molds for slip casting sanitary ware"
Dry it might sound, but a good read if you're trying to get hard, er - plaster!
The forms are coming out well, and the plaster pours very nicely, just need to see if they work well as moulds when the time comes!
With luck, a following wind, and a working printer I might finish the Art by Subtraction mould by Monday morning, which would just about give me time to have a working mould for a piece to raku fire next Saturday. How come timing is always so tight!?
Keep watching this space, to see how the mould fills up!