Firstly I managed to get hold of a large hexagonal nut, roughly 30mm in diameter. I filled the centre of the nut with car bog and sanded it flush when it was dry.
I then placed the nut, on the bed of a vacuum former and formed it around a HIPS sheet (High Impact Polycarbonate. This technique turned out better than I thought, making a perfect mould to cast a concrete bolt.
I experimented with just a basic cement and sand mix, in both wet, medium and dry consistencies to see what results I would get. Using petroleum jelly as a mould release.
However, the results were not as I expected. the finish on the bolts were very bubbly and inconstant throughout all concrete tests.
After finding an extremely low grit concrete, Used for bathroom floors etc, The results were much better.
These 3 bolts I am saving for the final piece, because they are free off of bubbles and imperfections. However, the reason these turned out the best was the combination of both the new concrete mix at a wet constancy and not using a mould release. Luckily the mould itself didn't break however, after the third cast a crack did appear.
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