Re: How'd they do it?

Posted by BH On 2014/4/1 8:56:04

Quote:
No.

As rusty as many of the cars of the 50s, 60s, and 70s could be, I had a couple of models from the 80s that I ran up to well past 100K on the clock, with no sign rust-through. I thought the manufacturers had learned their lesson, but I was wrong.

My 98 Monte Carlo has proven to be a rusty POS. I had to replace the radiator core support a few years ago (at 120K). The bodyman had to drill out the spot welds for the upper tie bar, but knocked the rest out with a hammer. Thr following year (and less than 10K later), I removed the lower body (rocker) moldings and I found the bottom of the front fenders gone and rear quarters rusted through. I also had to scrape and paint the floor pan, rocker and side cowl panels (with POR15) as all the spot welds and seams were festering with surface rust. I won't go into all the steel brake, fuel, and trans cooler lines that had to be repalced in recent years due to rust.

ELPO dip or e-coat is simply a more cost-effective way of priming. While it obviously offers savings in terms of both labor and material, it has actually caused some problems over the decades. For example, trapped air creates pockets up high on the car that never get coated, and the metal eventually rusts through - from the inside out. back in the 70s, I saw the tops of fenders of plenty of cars (regardless of brand) held together with duct tape. Yet, in more recent decades, I've seen more than a few vehicles with large expanses in the finish, where the paint had peeled off all the way down to the primer!

IMHO, the only thing that makes automotive finishes of more recent years last a bit longer is the polyurethane clearcoat, but that's only skin deep.

Over the years, I have come to believe that modern manufacturers select materials with an eye toward just making it through the warranty period.