: .....As it turned out the hardener pump
: supplied only half the required hardener.

My pumps sometimes burp, so I've switched to measuring epoxy in cups. Someone on the message board described this method a while back, at it works great for me:

One cup becomes the measuring cup with accurate markings, and the cup to be filled with epoxy fits inside it. It's easy to fill resin to the first line, and hardener to the second to get a perfect mix.

To make the measuring cup, one cup goes inside the other and then tablespoons of water are used to mark the cup in the right places.

John