West system epocy uses a weird mixing ratio, like 4 to 1 or 5 to 1, resin to hardener. this makes it far to easy to screw up the ratio, and when epoxy is mot mixed precisely, its characheristics when cured, are less than they could be. Softer, more flexible, less strong, ect.
I think West is just the brand most recognizable to boaters and lives on that marketing.
System3 epoxy resins
outclasses West, in my opinion, in all categories. They have a bunch of different formulations and hardener speeds, but everything but the general purpose resin is quite pricey.
This is a good low to midrange $$ epoxy with a simple 2 to 1 ratio and is pretty forgiving of slightly uncorrect mixing ratios:
Its only issue is when painting on the final coat on a prepped surface, it tends to 'fisheye', separate and leave a little crater/ depression, which can make getting a nice smooth surface, a curse fest. Dust and minor surface contamination must be reduced a lot to achieve a good final coating.
http://www.fiberglasssource.com/sunshop/index.php?l=product_detail&p=88
proper graduated mixing cups with accurate volumes are actually not easy to find. make sure the mixing stick you use can get in each corner of the mixing cup. Wipe the mixing stick until there are absolutely no swirlies in the epoxy.
Improper mix ration and incomplete mixing will cause a curse fest to end all curse fests, Proper mixing cannot be stress highly enough when working with epocy. Getting it wrong is a nightmare.
Do not let the hardener or mixed epoxy get on your skin. You can use distilled white vinegar to clean the laminating tools and mixing cups before the epoxy thickens too much. no Acetone or other nasty solvents needed.
https://systemthree.com/pages/literature
