Well, this was interesting.
I coated the three-gallon waterer and the replacement two-gallon one with epoxy. I mixed up enough epoxy to do both, and started with the three-gallon tankard. It went well. Then I moved onto the second, and it also...started off well. Soon I noticed the epoxy beginning to get thick; then it was like cottage cheese; then it ceased to be usable. This all happened over the course of about three minutes.
I recognized what was happening, and sped up. As you can see, the interior is a little chunky, but overall it's serviceable. What I didn't get to was the outside pan for the second one or the tops for either one. Fortunately, I was prioritizing my coverage--though I'm sad for the lost epoxy. It's too bad I didn't do some research first. Those two links suggest that under hot conditions (it was upper 80s when I did this) the working time might be as short as 20 minutes or so, and that's probably about what I got out of it. So for the future, only one can be done at a time.
I still have one more to do (the one I got off eBay) and more epoxy, so I'll probably give it another go--and maybe try to put the finishing touches on the two from this second effort. Next time I'll be working with a stopwatch, too.
