Making Molds for Rigid Urethane from Flexible 80A?

So, from doing a little more digging, it seems like the 50A is probably a better choice. We more specifically use MPFX mold silicone with a shoreness of 25A for our molds, so that will be a closer match for pliability.

We definitely use that mold release for a lot of applications. That stuff is great.