Woah, interesting! I’m in the UK. I get small amounts but I’ve seen them sold in packs up to 25kg / 55lb.If you can get aluminum and iron that fine, you can make thermite! Are you in the states?!?
“Two part” automotive clear coat is basically what I described. Many now are more like an epoxy to avoid the solvents but all the two part clears act the same- they turn to rock in the gun if you don’t clean it out because they chemically cure and don’t rely on solvent evaporation.
I’m pretty new to spraying, but one supplier recommended the G-100 spray gun or similar due to its quick cleanup and ability to spray thick gloopy stuff. But what you’re saying about turning to rock in the gun made me think of the G-200, which has a separate nozzle and cup for the catalyst - would that get around this problem?