Title. I’m looking for resins with the lowest Shore hardness, the lowest one I’ve found (that I can buy on aliexpress) is Resione F39, with Shore 60-75A. Ideally, I’d want to get something closer to Shore 30-40A.
So, failing that, anyone with a higher understanding of chemistry can explain what additives are usually added, resulting in a cured resin with greater elasticity?


For the size I want to print, a pure cube won’t cut it, but I did manage to make a form-fitting mold by making the cube hollow, then removing the cube proper, being left with the mold proper.
I’ve been spending quite some time trying to figure how to properly cut the mold into 2 or 3 parts in a way that I can actually close the thing and pull out the cured silicone without it deciding it’d rather stick to the cured resin. I’ve given some thought on making a single use mold, but I also gotta figure how to ensure its interior gets enough release agent to help me demold.
Can you share the model here? I can take a quick look. If you’d rather not share into the wild, then direct message me
I’ve never needed release agent with platinum-cure silicone as it’s not stuck to anything except itself unless it was porous. I have needed to lubricate bits of moulds that would have had too much of a vacuum if just pulled, though. Also, when I initially referred to coating the mould, I didn’t mean a release agent but rather something like PMMA (acrylic) dissolved in acetone to protect the silicone from the resin as described here: https://blog.honzamrazek.cz/2022/07/preventing-platinum-cure-silicone-cure-inhibition-in-resin-printed-molds/