Made a awesome FDM 3d printed silver cast mold. it shoudnt have worked as well as it did!currently the file is on onshape
feel free to mess around with it there
https://cad.onshape.com/documents/6b43fc94dc50b9063f2dc584/w/7d8f8d8c5c4b144bbfdc6a3c/e/c4b9a68d6dd848cb974f7495