Automotive Paint
Over the years automotive manufactures have been on a quest to lower manufacturing cost and just one of those areas is paint. By doing so, these improvements translate directly to their bottom line as profits.
The actual film thickness of paint is what I call
SCARY THIN, meaning it doesn’t take much effort to accidentally sand or compound through a layer. A layer of paint is so thin today it’s measured in microns rather than thousands of an inch.
Corrosion
How many of you can remember the days when a panel on a brand new car would show sighs of rust or corrosion in the first 2 years? You don’t have to go that far back because this was pretty much the norm in the 70’s and 80’s.
To combat this, car manufactures teamed up with paint suppliers like
DuPont to develop coatings and processes to greatly reduce or eliminate corrosion and rust through.
Microns
Microns are typically associated with either of the two following symbols; µ or µm
Just how big or small is a micron? 0.001mm, or about 0.000039in
To illustrate this lets put this in perspective by comparing a known and relate it to microns. On average, the thickness of a human hair is about 100 microns or 100µm.
1µ = 0.00003937in
10µ = 0.0003937in
100µ = 0.003937in
Now that we know how think a human hair is, see how it compares to the paint film thickness on most cars today....It's thicker than any individual coating applied and might be equal to all of the coating thicknesses combined!
Paint Application
Automotive paint is applied in layers and each one is designed to to work with out bond to the previous later. Today protective coating and paint layers can total 5 or more and at varying thicknesses. The photo below illustrates not only the coating but the average film thickness....
- Phosphate - 1µ or 0.00003937in
- Electrocoat or E-Coat - 25µ or 0.0009843in
- Primer - 25µ or 0.0009843in
- Base or Color Coat - 20µ or 0.0007874in
- Clear Coat - 50µ = 0.001969in
rops:^^^