Of the options available to remove paint from exterior surfaces of the body, I prefer chemical stripping over all other methods most of the time. Chemical paint stripper is very easy to control, does an excellent job, and does not damage or alter the surface of the parent metal at all. By using a razor blade scraper to skim the softened paint from the metal, the job of stripping an entire panel goes surprisingly quickly even with the “wait time” involved in letting the stripping chemical do its job.After a short ceremony to pay homage to the last vestiges of medium metallic blue color that remained on the car, I applied the first coat of stripper using proper chemical resistant gloves, respirator and eye protection. Allowing about 20 minutes for the surface coat to completely lift from the surface, I scraped the top layer of paint easily away from the surface with the razor scraper. Generally speaking, this would leave the primer layer(s) on the surface that would simply require a second coat of stripper to remove completely.
Once all of the original paint and primer was completely removed, I rinsed the panels clean with distilled water on a shop towel to remove any stripper residue and neutralize the stripper. The result was nice, bare metal panels that were ready for a close inspection and evaluation in order to begin planning the repair and prep work required to plan for primer and the sequence of conventional bodywork to come.The panel evaluation work is best accomplished without any sort of prep coatings or etchants on the panel so that even small details are not lost or masked. This is particularly important on 40+ year old muscle cars as many manufacturers had not yet adopted immersion priming methods or anti-corrosion primers on all surfaces of the body. EDP primers were still decades away before the last genuine muscle car rolled off the assembly line. A close inspection is often remarkably enlightening as was the case here. In fact, what I realized based on my inspection was I had a very unique opportunity to educate on the hidden evils that can exist under “survivor” original paint or older restoration work. As such, the next section will cover this critical information with some very graphic examples of “what lies beneath” in more cases than you might imagine.
|Aircraft stripper is a favorite of mine to chemically strip the last bit of factory paint from the rear quarters. One thing to notice here is how relatively "rust free" the left rear quarter appears before the stripping work begins.|
|The first coat of chemical stripper very quickly starts to lift the original finish and is very easy to manage as evidenced by the lack of runoff of the stripper to the side of the quarter.|
|The top of the rear quarter has had its first round of chemical stripping complete and you can start seeing evidence of more extensive rust being exposed. We will detail this discovery more in the second half of this article.|
|Moving to the front half of the quarter, the stripping process is identical and equally efficient. A quick few minutes with the scraper and the second coat is applied over the same area and left to work for another 20 minute soak period.|
|After scraping off the second coat of stripper, the front half of the quarter is clean and down to bare metal. Again, we see more evidence of the extent of surface rust that existed under the original paint and primer.|
|With all of the original paint and primer removed, the left rear quarter is completely exposed for a close inspection.|
|Moving to the right side quarter, the same stripping operation is applied. In this shot, both the top and front half of the quarter has been completely stripped.|
What You See Ain’t Always What You Get!
Nowadays, there is a tremendous amount of hype thrown around about preserving “original paint” as much as possible and avoiding stripping a car to bare metal during a restoration. Well………bullshit.
Quite simply, with original paint left ANYWHERE on a body during restoration, you simply don’t what you don’t know because you can’t see what can’t be seen. As it turns out, the rear quarters on the Boss were a perfect example in the most exemplary way. If you look at the pictures below, you will see there are hints of what most describe as “minor surface rust” starting to peek out from the very weathered original paint.
As each layer of paint and primer starts to come off the panel during the stripping process, more and more evidence of surface rust starts to become exposed. In fact, until the last trace of the base primer layer is completely gone, the full extent of the rust propagation is hard to imagine. In fact, a general rule of thumb is that for every spec of rust you see perforating the surface of “original” paint, the extent of rust repair requirement is roughly 10-15 times larger in scale. In other words, if you see a ¼” rust spot on the surface, the expected repair area will be approximately 2.5 to 3.75” across and often this can be a conservative estimate.
This simple fact is shown in undeniable and explicit detail in the following photographs of the tentacles of rust spreading widely across the panel that were completely hidden beneath the original finish. Only until the panels were stripped to bare metal was the true extent of damage revealed. Without this revelation, there is no way a proper assessment of the requisite repairs can be completed and any hope of a successful restoration of these surfaces is simply impossible.
With that, the lesson is to strip absolutely EVERYTHING to bare metal during a restoration to make absolutely sure the hundreds of hours of labor and untold thousands of dollars of investment you will make will be spent with maximum effect and long-term return. It really is that important.
In the next update, I will document how to deal with the “ugliness” we have discovered. Also, I will describe a simple process to reliably detect almost microscopic rust and how to eliminate it permanently. Also, we will start getting into the repair of some small and moderate sized dents and dings. Until the next update!
|A bit further rearward on the left quarter and this "rash" of rust became more and more visible as each layer of paint and primer were removed. If you look closely, you will see a fair amount of primer is still left in the rusted area.|
|With the top surfaces of the quarter stripped bare, you can clearly see why it is critical to avoid getting caught up in trying to save original paint in a full restoration. What you can't see can definitely hurt you!|