Thanks for your response. Her some additional informations.
First the picture Andreas asked for:
cw_5compTetra midturn (2).JPG [ 1.98 MiB | Viewed 960 times ]
Here the mold for casting. The Oomoo30 to very strechable. It was not complicate to find the best position for copying.
For the complete puzzle I need the center 6 times. The corners 4 times. To make the copies it took 75 minutes. I didn't make any sandings on the masters before.
cw_5-molds (2).JPG [ 1.83 MiB | Viewed 960 times ]