[toyman]

67hydro - CA is the leader in environmental laws and regulations. That's why when you buy a new car it costs $1000 more than everyone else, for now at least. Anyway, here's my take.

I use PPG Omni AU (Acrylic Urethane). It is less expensive than PPG's main product line, but does take an extra coat for good coverage, especially the yellow. Durability of Urethanes and Enamels? I'm tapping into info I've stored from long ago, and I'm not a chemist, but.....the catalyzed (hardener)Urethanes dry thru a chemical reaction and the enamels (bear with me as I forget the tech terms) basically air dry. The other difference is that enamel is more finicky than the AU's. When I used to shoot enamel I could count drops from the mixing stick (instead of using a viscosity cup) and it was 'close'. Once you shoot enamel, you get what you get, where the AU's are relatively easy to sand & buff. (ie: easier to get rid of imperfections such as runs and orange peel) The AU's are also more UV stable. AU's are very easy to mix and spray.

As far as epoxy goes, I use that for my primer. It is very tough and is a great undercoat over bare metal. Some like to use a wash or etching primer over bare metal. Wash primers do a good job of etching, but aren't very tough, and you can't shoot epoxy primer over wash primer. You can, however, etch the metal before you shoot epoxy primer. PPG has a product called metal prep to do this, and is compatible with epoxy. The best of both worlds.

That's what I have from memory. Whatever you do, use a fresh air system, or at least a respirator with fresh cartridges and good ventilation. These chemicals can kill you if you're not careful. And, they don't stop being dangerous after you spray. They will 'off-gas' for day or so after you finish. Let your parts sit for a day or two and ventilate your area well. Wear you respirator. Isocyanates (sp?) found in the catalyst can enter your body through your skin, eyes and nose, so be careful!!!!!