Over the weekend, I made my first RTV mold and cast my first part (huzzah!). I'd like to keep the mold for future use, to cast more parts when needed. What's the best way to store my mold? How long will it last? I guess I expected it to last a long time but I've noticed that it gives off some sort of oil, which leads me to believe it has a definite shelf life. For reference, I used Alumilite QuickSet silicon rubber to make my mold. Is there a better molding material that will last longer?
Bob