I should probably get it out of the way right now, since it always comes up.
I hate base-clear on old cars. There, I've said it.
Don't get me wrong, I am not knocking base-clear systems. I have nothing against them in the right context. Base clear is a very efficient system, giving very high gloss and reasonable repairability. I just think it looks wrong on our classic cars.
Let me back up and talk a bit about paint systems in general.
A single stage paint, whether it is nitrocellulose enamel from the post-war era or modern polyurethane, is for lack of a better term, paint. You mix it up and shoot it on. Technique aside, it is the same stuff, top to bottom, through and through.
Base-clear, also called two-stage, employs a thin layer of color and a thick layer of clear-coat on top to give gloss and depth. The advantage of base-clear is in material savings and time. The color coat is only thick enough to cover the sealer and requires a very small amount of actual color. The clear is there to protect the color and to give the depth and gloss. Lots of depth and gloss.
Base-clear systems are quick to apply and are the best choice for production shops and OEMs. They can be either very simple to repair, or very difficult, depending on color matching and the shape of the panels being fixed. Rather a double-edged sword in that account.
I don't like to shoot them for two reasons. The first is that the application techniques employed are very different from that with single stage, requiring a different gun setup and a rather steep learning curve. I can deal with that.
The main reason I dislike shooting base-clear is that I think it just looks plain wrong on our old British cars.
It is too just glossy, and, to my eyes, looks artificial, plastic-y, if you will. I can walk down the line at a car show and spot base-clear paint from across the lot, and it always makes me ask myself, "why did he do that?" So often they were sold on that system by someone at a production paint shop, someone who likes the look of their bottom line.
A properly applied single-stage paint job can look just as glossy, but will not have that "wet"or "plastic" look that just rubs me the wrong way.
Many people think that more gloss is a good thing, and they are welcome to that opinion. If an owner likes that look, by all means go with it. It is their car, and should make them happy.
Still, to me a British sports car will never look "right"with clear-coat on top.