Allpar Forums banner
1 - 1 of 2 Posts

· Super Moderator
Joined
·
12,501 Posts
Ziebart is rubberized undercoating on the bottom of the chassis, not primer paint.

The problem of peeling paint is so common, it get mentioned periodically here. I should write an article rather than retype, but here goes:

In the late 1980s, as a measure to reduce VOCs (Volatile Organic Compounds) that are harmful to breathe, paint manufacturers introduced a powdercoat for automotive primer use. Powdercoat is hard, durable, applies evenly, but it has one flaw - it is highly reactive to ultraviolet rays and oxidizes.

Now, the paint manufacturers told the carmakers that they could apply finish paint right over the powdercoat. So they did, without properly testing it themselves. However, they also apply the finish paint even thinner now. So the UV rays make it through the finish coat and within a few years the powdercoat underneath oxidizes and lets go of the finish coat in large areas.

The fix is to use a regular primer between the powdercoat and the finish coat, so as to block UV rays. So do not paint the finish color on the original primer unless you first sand the powdercoat and put a good thickness of primer down, then two finish coats and two clearcoats.

The body shop I use decided to sand my car to the bare metal, start with an etchant primer, then regular primer, then finish and clearcoat. When I got rid of that car 10 years later, the repaint still looked like new.
 
1 - 1 of 2 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top