Good info and that makes as much sense as anything Bill. What I had fail was the quick set epoxy that is thick. I have used it a lot and this was the last of the of that batch. I had no failures before so I have to assume it was something I did and not the epoxy. Air makes as much sense as anything.

I just mix it with what ever is handy. I do very small amounts at a time and usually stir it with a scrap of wood. If I have a something like a putty knife handy I will fold it as John was saying, but not typically.

As for marine epoxy I like Raka because of the lower cost. It is thinner than any other epoxy I have used which can be good and bad. I could not mix it on something flat. To thin!