Good to point out the difference in epoxies. Polyester based is not the same as the better grade types. Read labels if in doubt. Poly resins aren't structurally at the level I have implicit trust in. Not saying it won't perform satisfactorily, just isn't as strong and reliable. And yes, mixing the catalysts (fast, medium, slow types and the ratio) determines set time and ultimately, strength of the bond. Using different set-up speeds is to facilitate different work environments and materials. Vertical or overhead surface work on a vessel requires little run /drip and fast set. Horizontal surfaces can be mixed a bit cooler so set-up time is greater. Marine-tex is just a 2 part formulation that is mixed per instructions and goes right to work. Strong and effective stuff I've grown a liking to.
