Is it necessary to vacuum or pressure the Water Clear and Flex 80?
Not in order for it to cure but yes in order for it to cure with absolutely no air bubbles present within the cast piece as well as the best physical properties. Both of these materials start out at a higher viscosity (thicker) than the other Alumilite resins. Therefore, when these two materials are mixed, the viscosity (consistency) of the material does not allow the air bubbles to freely find their way to the top of the cast piece as the other much thinner resins do before the material cures. These two materials feature a slightly longer open/work time in order for you to either vacuum and/or pressure cast to eliminate all of the bubbles within the casting.
