After reading builder's comments about the difficulty of measuring epoxy by volume (one worker declared the metering pumps "useless") I decided to try mixing by weight. I bought a small gram scale on Ebay. It seems to be a good way to mix small quantities. I just got my Shearwater 17 kit yesterday, and I only had time to do two Puzzle joints before work. 10g. resin, 2g (West Systems) hardener, neat as a pin, little waste, and accurate! I plan to use a larger postal scale for larger quantities, when I get to using the Mas.