I just finished casting the cassette and the top in silicone. Man.. did it take a long time, and a LOT of silicone. I think I ended up using about half a gallon to do the two items. It wasn't that bad, it just look a lot of mixing and pouring of different bottles of silicone. I really should get a gallon sized containers.
I made up forms from foam core board, and secured them to the bases. The boxes work really well for the silicone and they are really easy to rip apart later to get the mold out. I painted the parts a bright green as I feel it makes it really easy to find imperfections on the surface of the parts, and goes on really thick to make everything smooth.
The green smudges inside the cassette are from my fingers and wet paint.
