I have been thinking about making some things like ceiling medallions and other applied designs but rather than cut each one out on the bot I thought of making some type of mould and making the positive out of some type of pourable foam because you want something lightweight to stick to the ceiling rather than some heavy plaster object.
Is anyone doing anything like this? Where would be the best place to start to learn what is the best material for the moulds and for the foam? Is there a specific forum or place to gather more information?