Would like to preface this by clarifying that me and my team entered this with very limited background knowledge in casting and molding making. That said, definitely made the mistake of thinking working with the material would be a lot more straightforward and smooth sailing that the reality turned out to be. Here is a snapshot of the Silicone vs Latex question we started with.
Silicone is much pricer than latex, but the trade off is that (in terms of making a mold) it is reusable and doesn’t require hours of paint on process. The issue comes in that using a latex cast using a Silicone mold would have left the mold unsuitiable for being used with silicone in the future due to a unique interaction between them. In short, silicone will not cure when exposed to latex, to the extend that even having a box of latex gloves in the same room can prevent proper curing. If latex was ever used in our mold, we would never be able to go back to using silicone in it. Early on the weight was scaled much more towards keeping our options open (rather than just plunging forward and seeing where that leads us) which led to a lot of overly cautious decisions that came back to bite us. Even more significantly, latex needs to be able to breathe to dry, and therefore would have to be painted on in layers somewhat to get the details of the mold-a process that would have taken hours compared to what we believed was simple pouring for Silicone. Silicone may be better for making reusable molds but the high price of it forced us to be drastically more material conscious and conservative on rapid prototyping than in retrospect would have been ideal for testing. It led to every test being a 50 dollar investment with very high stakes-leading to a lot of delays in the interest of decision making, repeated shipping as running out came up despite us trying to use as little as possible, and just an overall suffocation of the prototyping phase. Silicone also has other challenges. While Latex would have prevented the mold from being used with silicone, casting silicone in silicone also runs the risk of them sticking to eachother if a release agent isn’t used properly. The material conversely doesn’t like sticking to most other things, including most make up and painting options. This led to another axis of struggles, in that our past knowledge of color application needed to be changed to work with silicone specific paints, and led to a lot of our background knowledge no longer being as helpful. Silicone samples and experts were also much harder to come by locally which led to a lot of this work being done on the trust of information we are reading online applying in our case. Silicone is a wonderful material but for someone who is inexperienced, going for the liquid latex and just letting yourself fall fast may have proved more appropriate for our uses.