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Dozerboss, I don't think there is any question that the urethanes will give the best overall performance, particularly with respect to fade and chemical resistance. I would put synthetic enamels, acrylic enamels and urethanes in that order of increasing performance. Not surprisingly that is also the typical order of increasing cost. The urethanes (and enamels with hardeners for that matter) are also the most toxic to use due to isocyanates in the hardeners. The proper respiratory equipment for these materials is a positive pressure fresh air breathing system. The cost of this safety equipment is typically a minimum of $400. This would normally be beyond the budget for the casual painter who just wants to paint his tractor and is not in such a business. While the extra cost of the low-end "economy" urethanes can be justified based on improved performance, the additional safety equipment necessary to use them usually cannot. I don't recommend anyone use the urethanes, or even enamels with hardeners, without that fresh air breathing apparatus...not even for a one time use outside. That's how important I think the matter is. About the only other reasonable alternative is an acrylic enamel w/o hardener. That's better than the synthetic enamel "tractor paints", is better than the OEM tractor enamel (at least that provided on vintage tractors) and can be had at a reasonable cost and used with only normal safety equipment. If someone has the proper safety setup, then by all means they should go with either the urethanes or an acrylic enamel with hardener. My own past experience with higher-end acrylic enamels (Centari, Delstar) w/hardener has been excellent over a long period. They are even a little more expensive than the economy urethanes. My more limited experience with single stage urethane indicates that it is more susceptible to chipping than an AE w/H. I am finding that out on my AC-B. That's probably because the film is a little harder and more brittle. I have not yet tried a flex additive in it to try and minimize this. I have noticed it particularly where the hand crank sometimes rubs against the radiator cover opening. I would not have expected the paint to chip there but that is what happened. It also seems to chip more easily when installing pre-painted bolt heads and nuts. I once painted a snow plow with PPG's Durethane polyurethane. At the time it was PPG's equivalent to DuPont's IMRON. That's the stuff used on planes and trains. I mistakenly thought the harder film would be more resistant to heavy scraping and scratching when plowing a long gravel driveway. It may be harder than an AE w/H but it cannot stand up to that kind of use. I noticed no real improvement for the added cost. I am not a fan of BC/CC. At least not yet. Three past vehicles I have owned (all OEM BC/CC urethane paint - 2 Honda, 1 Ford) have, after about 8 years, had the clear coat peel away in patches sort of like a snake shedding it's skin. Looks terrible. The truck I currently have is black BC/CC. As far as I know, all new automobiles nowadays are BC/CC. I have noticed that light scratches not deep enough to effect the base coat show as white on black. I got several such scratches in going through an automatic car wash. They show up big time. The "damage" would not be as apparent with a single stage black. I think most of the car painters use BC/CC because 1) reportedly, it is easier to paint a metallic finish and get a uniform appearance and 2) it provides a better match with the OEM paint if not doing an overall. Since the bulk of the autobody business is repair work with mostly metallic finishes, it's either use BC/CC or lose work to the competition. I cleared much of the single stage urethane I used on my AC-B because I think that makes the decals have a better appearance and serves to protect them. SimiIar to the scratching on my black truck, where the throttle lever rubs over the steps of the throttle quadrant it is whitish rather than orange. This is also noticeable to a lesser extent where the throttle and choke rods pass through their guides and rub a little. Again that would not happen with a single stage. It would dull but at least it would be the same color until it completely wore away. I am not convinced BC/CC has any real overall advantage over single stage for most tractor work.  Rod
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