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Hi Don, I'm no particular fan of base/clear so my comments are admittedly biased. The clear is applied during a time window as stated in the tech sheet for the particular basecoat product. For example, PPG's OMNI MBC basecoat indicates for the basecoat to dry at least 20 minutes but no longer than 24 hours before applying the clear. Other lines may have different time windows. My limited experience with applying clear indicates that it is no harder than applying single stage color. The issues of runs and orange peel are the same. Clearcoats can be sanded and compounded to correct problems in the clearcoat, provided the configuration of the part is reasonable for power compounding. Many tractor parts are not. Clearcoats are almost always urethanes so they require an isocyanate-containing hardener - and for safety, a supplied-air breathing system. Base/clear systems are said to be easier for the beginner to use. I question that in most cases, but I do agree they would be easier for the application of metallic finishes, common on cars but not on tractors. The base/clear systems are more expensive. Plus it takes longer since there are more coats (perhaps twice as many) to apply - and more chances for error. For the home-shop DIY painting outside, having to deal with two different time windows (1-epoxy primer, 2-basecoat) can be difficult as far as scheduling activities around unpredictable weather. In my opinion, base/clear systems are best utilized when panel-matching a late model automobile which already has a factory base/clear finish. For over-alls and tractors, I see no compelling reason to decide on a base/clear system, unless a metallic finish was desired. I suppose if you want to get picky on show quality, applying lots of clear, coupled with lots of sanding and compounding can result in a distinctively "deeper" appearing finish. But how effective that is for many tractor parts is open to some question. I've applied clear over single stage because I think the clear gives cut decals a better, smoother, appearance and provides some limited physical protection for them. However, on my last fender-painting project, I got a little orange peel in the clearcoat that was not in the single stage color. I would have been better off to stop after the color and forget about the clear. In that instance I was clearing over single stage simply to be consistent with the hood where I cleared over the cut main hood decals. The fault was mine in the application on the fender, but it is a reality that everyone should consider. More coats = more risks of application errors messing something up. In my case it wasn't serious enough to do anything about and resulted in only a slight disappointment on my part. But it could have resulted in some significant rework if it had been worse.  Rod
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