A restful day but I have done a bit of casting. I've tried many way to obtain a smooth accurate relief including pouring plaster onto the painting surface, and cutting or carving images from solid blocks. This time I wanted to cut the shapes from foamboard and cast the plaster in the holes.
The first results were not promising, there were large air bubbles, and keeping the surface flat and even proved problematical. The process was also very messy. It's naturally difficult to calculate the volume of plaster needed for pouring into a mould, so it overspilled.
I've just cast a second set, this time casting a mirror image, so the visible part will be the underside which is always better looking. The foamboard, though excellent to mark and cut, does bend and deform easily and it is difficult to demould the shapes. The card is sensitive to water so after just one cast the moulds are already showing signs of deterioration.
When making the Keyholes picture I concluded that the best system was so cast a solid block and carve, but that makes for a heavy picture, and it's not easy to guarantee a strong bond between the plaster and the wood panel surface. A picture should ideally withstand being dropped. I like to test every new process to destruction!
It's all a lot of work. At the moment I'm more obsessed with perfecting the process, less so with the artistry. I might not use many of the relief parts I'm casting because impressive as they look, they might not increase the verisimilitude of the painting. It's good to gain the practical knowledge and skills though.
