Here are three short videos that illustrate the process of using thin metal plates to divide plaster before it hardens, improving accuracy and saving effort and cleanup.
Since Fall 2014, I've been developing techniques for building geometric shapes from plaster that avoid a few of the inconvenient aspects of traditional methods. Using saws generates dust, damages the brittle plaster, creates noise, and is limited to very planar changes.
I noticed that thin metal plates can be inserted into the gelling plaster and would stay in place. After the plaster hardens normally, it breaks apart cleanly where the metal plates are.
Aside from being a nifty trick in its own right, this discovery is leading me to very complicated shapes in plaster that afterward function as ceramic slip casting molds. The resulting shapes would be very tedious to make otherwise.
In another blog post I share an academic paper I wrote relating this plaster forming method to abstract sculpture processes.