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?
You need a silicone based resin. TPU based are 65A or stiffer. Stratasys or Formlabs make these down to 25A, but they are expensive. Very difficult to print most shapes as the print inherently sags. They print very slow, 30 second first layers.
Spool3D elastic is 40A and inexpensive.
https://spool3d.ca/spool3d-elastic-resin/