Originally Posted by
Mike Cutler
From the system 3 website.
"All System Three® epoxy products can be measured by weight or volume. Pourable products can easily be measured by volume, but paste and putty products are most accurately measured by weight. The correct mixing ratio for your product can be found on the product page."
I have used gallons of System 3 epoxy through the years, and unless something has recently changed, I have mixed it in epoxy cups, following the ratio. 2 parts resin: 1 part Hardner. I have been doing it by volume.