To make this part I needed a large silicone mold. To make the mold I printed two 1/8th sections of the mold negative, glued them together and then cast 4 sections of the silicon mold from that. These I then joined together with more silicone and another Form1 printed 1/8th alignment section.
The 4 seam lines you can see on the final part are actually the glue line in the center of the mold negative quarter. Gluing the silicone quarters together using a printed alignment piece worked well enough that those seams are hard to see.
The picture shows the mold 1/4 negative and a resin vat for scale. The full silicone mold is on the bottom, and the part is on top.
I used fiberglass re-inforced jesmonite, the wooden platform it’s all siting on is my home-made vibration table to make sure the glass jesmonite sludge mixture settles into the mold properly.
See the video link below for a fuller description of the process, including a description of the vibration table.
