Remix from https://www.thingiverse.com/thing:2386601

I wanted to experiment with using 3d printed molds to cast concrete sculptures so I took the tortoise from above and make it into a mold. It worked well in the end, but melting the PLA off from around the concrete was a major pain. This process is destructive to the mold. Perhaps printing in a flexible material would be better, but it didn't turn out too bad for experimentation.

Slow and careful melting of the PLA with a blowtorch and pulling the plastic off with pliers worked to free the concrete.

NOTE some support is required because there are some overhangs. I was able to carefully pull the supports out with long needle nose pliers. The neck/head hole was the hardest part to clean.