Hey Trent. Here is a picture of my original formwork for the piece. The plastic I used for this mold is fluorescent light panels from my local building material supplier. We adhered the light panels to the melamine with silicone. We added more bracing to the legs of the form while spraying and laying up the backer. We screeded the inside of the piece with a scrap piece of forming. It's actually a very similar process to the one posted by Charlie Brown for his B.B. table.
The piece is super strong as well. I haven't tested the full weight bearing capacity but here is a pick of me standing on it.
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