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Hi Jim, Thanks for the kind comment. I think you are referring to my post in this thread. To me the answer is still up in the air regarding chipping. I have used hardened enamels over many years - but on cars not tractors. My fairly recent experience with a true urethane on my own tractor indicated a chipping concern as did my experience with my '02 truck. I applied the low end urethane (PPG OMNI MTK) to my tractor but the truck was an OEM urethane. I can't say that I have experienced any chipping problem over the years with the hardened enamels. But then I never experienced the similar situations as on my tractor and truck - chipping when the paint film is under a high stress at a corner or edge. The only thing I noticed with the hardened enamels was over a period of years there would be some noticeable "sandblasting effect" on the rear portion of the rocker panels and lower rear quarters, most likely due to travel on dirt roads. I wouldn't call that chipping although some might. It certainly is not the type of chipping I noticed on my truck and tractor. I definitely think you ought to at least use a hardened acrylic enamel since you have access to the proper breathing equipment. The increased chemical resistance alone that you get with it (think spilled gasoline or diesel fuel) would be reason to go that way, IMO. I just don't know if a true urethane is that much better, especially if it is more prone to chipping. I certainly would stay away from synthetic enamels, especially unhardened ones. If you use those and your tractor is red, it'll be pink in a years time outside. I had a Pontiac car once for about 10 years after I painted it a brown with a hardened acrylic enamel (DuPont's Centari). It was always outside, never garaged. It looked about as good on the day I got rid of it as the day I painted it. My working tractor (urethane OMNI MTK) is approaching three years and also looks as good as when it was first painted (at least those parts that were painted :o)). It is always outside also, never housed. I run the tractor through overhanging branches at the edges of my fields when mowing. No chipping caused by that. Even the areas that normally get rubbed, albeit lightly, do not chip. I am thinking of where the throttle and choke rods rub against their guides and the notches on the throttle quadrant that are rubbed all the time. No chipping. I'd call that wear that you would expect from any paint. The actual chipping just seems to be in applied high stress areas at edges and corners. What I don't know is if that is characteristic of urethanes, or at least if they are worse than hardened AE in that regard. I suspect they are worse but don't really know. It may also depend on quality level and cost but I refuse to treat my tractor like a show Mercedes - couldn't afford it even if I wanted to. Frank Stalfire from DuPont mentioned the use of industrial/commercial line urethanes a while back. I have no experience with or knowledge about them but they could be something to look into, provided they are readily available in the right color locally and at a reasonable cost. I'd at least go for a hardened acrylic enamel. All in all I think it would be better than the original, which I suspect was an unhardened synthetic enamel. If you're looking at Martin Senour (NAPA), you probably can find out the color code (if you know the name) and available chemistries here. Just search on your tractor brand. They also have a cross reference from the codes of other paint manufacturers at the same place. I wish PPG and DuPont had that feature at their sites. Regarding your other question, I am not aware of any two-part epoxy topcoats for tractors or even cars for that matter. I know some exist, more likely in industrial/commercial lines. I once used such an epoxy topcoat to paint an aluminum boat hull. Worked slick. Epoxies have a reputation for excellent adhesion. I would expect that topcoat color choices would be quite limited though.  Rod
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