Mike,
The problem with the frame in question is not the modern paints. It is in the application and/or the compatibility of the paint and primer. I have seen frames like you describe. I had one here about a year ago that was freshly painted and the owner was still in the process of putting vintage parts on the frame, and the paint was already useless because everywhere a part was inserted or clamped on the paint was tearing away from the primer. The paint an clear was so thick that it was comming up over the clamped on parts as if it were a wave of semi-wet clear. This happens for one reason I can see. The painter opts to use white primer under the paint to accomplish a base for a flamboyant finish. White primer does NOT work, from my observations. A thin layer of white Imron is much better; tougher and much thinner. The flamboyant color can be sprayed over it while still wet, which further aids the bond between primer, base color, and paint. Everything about painting bikes has to do with bike specific painting skills and experience. One thing that I've found to be universally true; never try to save steps.
Brian Baylis
La Mesa, CA
Reading the threads about painting, preserving, and clearcoating got me to thinking about modern paint jobs.
I have recently come across a few steel frames with disturbing rust issues. These have all been modern frames, out of the CR timeline, but all built by "keepers of the flame" and painted by a universally acclaimed painter. What I've seen is that rust begins at a tiny chip or break at the paint, but then spreads remarkably far under the paint. In a way I see this as a drawback of using modern paints. On an old PX 10 the spot would be much more likely trust and stop there. With the tougher modern paints, the film strength is sufficient to both trap moisture and remain intact as rust travels beneath it. In fact, on the frame I'm currently working with, the ripples in the paint are still remarkably tough. If the paint had been applied by a lesser painter I would have assumed they were slight runs and left them alone, but knowing this painter's work I knew that there had to be a problem under the paint.
Obviously, this kind of thing can be prevented with serious vigilance and maintenance. But what about those fine frames owned (and less frequently serviced) by less passionate owners? It's hard to fault them when they've been sold on how durable the paint will be. I've got one in my shop now that isn't terribly old, hasn't been ridden enough, and has been reasonably well cared for, but the extent of the ripples in the paint lead me to suggest that the owner have the frame repainted.
Mike Fennelly