After finishing up Furi and a few other minor tasks, we finally returned to the Big Apple. We’re still hopeful of completing everything by 2025, as long as we can first ensure the workload on the body remains manageable.
From the outset, the Big Apple was defined as a correction project, which meant relatively conservative work (especially in terms of cost). However, the car’s unique characteristics inevitably necessitated different approaches to the work. For me, the most critical component is the body, and that is the first thing we needed to understand.
Overview
Let’s review why his case is so special. Big Apple is a 1997 S 420 filed total loss in New York in November 2001. At the time, it was leased to a user from Greenwich, Connecticut, by MB dealer Helms Bros. in Queens.
During the initial inspection, I noticed abnormal readings on the car’s roof paint, with some areas reaching over 1,800 µm—almost 18 times the factory paint. Considering the location of the damage, the date of the total loss, and the owner’s address, I speculated that the car may have sustained damage during the 9/11 attacks. Of course, even if that were the case, it wouldn’t be significant.
Further anomalies included an incorrect hood. All North American 1997 S 420s were equipped with activated carbon filters, hence the grille of it on the hood, but Big Apple’s lacked one. Further inspection revealed the hood came from a Japanese car, as evidenced by the Japanese-spec stickers. Therefore, the hood had been replaced.
Using this as a clue, further inspection revealed collision repairs on the left front corner of the car, which had been crushed to approximately the top of the left front axle. The crude sheet metal repairs lay beneath thick, cracked filler. Additional bodywork was now a foregone conclusion.
Unfortunately, the problems didn’t stop there. Repairs were also found on the right rear corner, with damage to a corner of the trunk lid and the entire area around the taillight. Once again, it was a case of lazy repairs and extensive filler. The right rear door also appears to have some filler.
In terms of paint readings, the right side and roof were repainted once, and the left side was repainted twice. The thinnest paint is about 170 µm, and the thickest is about 300 µm. The previous painter was actually quite lazy and didn’t use filler to fill any dents. This was a boon for us, as we didn’t have to spend too much time filling, and the dents were clearly visible.
Since one side had already been painted three times, with uneven thicknesses on both sides, and many areas needed to be sanded down to bare metal for repair, the only acceptable approach for Big Apple was to remove all the paint and start from scratch. This was the only way to ensure durability and consistent paint thickness. On the positive side, this also presented a good opportunity to explore another level of restoration—for cars with original paint that hadn’t experienced any accidents, we advocate retaining the original E-coat or even the base coat. We considered re-electrophoresis or spray-priming a risky amateur endeavor. Now, “real” restorations, like those being done in Italian shops, are being forced upon us.
Plan
A preliminary inspection before disassembly revealed the following panels needed to be replaced:
- Left front fender
- Right front fender
- Right rear fender
- Hood panel
- Trunk lid
This also included the front and rear bumpers and other required exterior parts. Parts collection began in the summer of 2024. Finding qualified, undamaged sheet metal is becoming increasingly difficult these days, especially for the front fenders and, as we’re discussing, the trunk lid with its narrow license plate. We collected the right front fender almost exactly on time, from a 1991 500 SE, after nearly a year of searching. The remaining parts came from a North American 1995 S 500. None of these parts had any repair history, making them ideal replacements.
The difficulty of this job lies in the fact that it’s a complete body job, not a full restoration project. The former requires the removal of all paint, while the latter requires that nonessential parts remain on the car as much as possible. After all, this isn’t a simple car; it’s not as simple as pulling up the carpet and painting the entire shell. I believe that removing the CAN bus and factory insulation paint shouldn’t be done except by amateur shops who like to overdo things (happily expanding low-tech jobs). Furthermore, the car only has repainted the exterior, while relatively interior areas, such as the door panels, still have their original paint. Therefore, it’s necessary to protect the interior from unnecessary damage while expanding the exterior work.
Therefore, the work was divided into two phases, depending on whether or not interior work was required:
The first phase involved interior work. The decision about which areas required interior work was based on a variety of factors. First, the color of the replacement part. For example, the donor 1995 S 500 was Black Pearl, while the 1991 500 SE was Brilliant Silver. The Black Pearl replacement panels naturally required repainting. Although the Big Apple was also Brilliant Silver, for consistency and corrosion protection, the decision was made to remove the original interior paint from both fenders and repaint them.
Second, the order of work was considered. Some panels should be installed on the body before sheet metal work and should not be removed after the body work was completed. This meant that there was no opportunity to paint these obscured areas during the subsequent body painting process, so it was best to paint them before installation. A typical area is the area behind the front fender where it meets the front door. The hood, on the other hand, falls outside this category because it can be freely moved when painted alongside the body, eliminating dead space.
Third, the production process for each vehicle cycle also differed. On MY1996 and earlier cars, the inside of the trunk lid features an additional matte black coating. From MY1997 and later, the inside of the trunk lid is painted the body color. The first option is a sophisticated approach for older cars, but it’s not very durable. The second option is more cost-effective and, thanks to the clearcoat, more durable. We will be changing the inside trunk lid color for the Black Pearl, as the Big Apple is MY1997.
Parts requiring interior work begin first, prepared in advance and then installed after the bodywork is complete.
The second phase involves exterior work. The goal is to sand off all coatings, including the E-coat, and then paint. Unlike typical projects, this time, since the entire left fender is being replaced, work on the engine compartment is also being performed. However, this area is still considered “exterior” because it is accessible. The exact condition of the vehicle and further details of its repair history remain to be revealed in the upcoming work.
Interior Work
First, the four panels to be replaced were stripped. With the exception of the right front fender, which had been repainted once from a 1991 500 SE, the other replacement panels were all original paint. The goal was to remove the exterior paint as thoroughly as possible while preserving the interior paint as much as possible, as the interior contained not only paint but also factory high-elastic PVC for rust prevention and improved NVH.
Then, the “outside” areas that did not require painting were masked and sprayed with an epoxy zinc-rich etching primer. Simply put, only the outermost surfaces did not require painting, as they were still undergoing PDR. The hood was not included in this process due to a special process, as it already had a black coat of paint on the inside near the windshield. Therefore, the correct order of work was to paint the hood with the body paint and then paint it black.
The priority of preparing the replacement panels was to install them on the body as quickly as possible and then freeze them there. Because this involved structural repairs, the positioning of the hood, bonnet, and bumper on the left front could be unpredictable. Therefore, structural repairs had to be performed in conjunction with the replacement panels to ensure that tolerances were within reasonable limits. This means the fenders will be installed quickly and won’t be removed, so the insides need to be painted in advance.
Exterior Work
Instead of the standard paint stripping, I decided to try a different approach this time. A fresh approach always gives me more motivation. In the past, we’d strip the paint as usual, apply primer promptly, and then perform PDR. The purpose of the primer is to prevent rust from forming on the panel.
However, as is typical with primer, it has a fairly low gloss, making it difficult to spot even small dents. This often led to dents being missed after sanding with #800 sanding mid-prime. Therefore, a diligent practice in the restoration industry is to apply a clear coat to the primer to create a sufficient gloss for PDR before removing all the paint. This is an advanced method, but also quite time-consuming.
However, in my experience, performing PDR on a painted panel compresses the paint. This means that after removing the dents from the painted panel, the paint and panel appear flat, but the panel itself does not, as some areas of the paint have been compressed. With this paint removed, the low spots that once needed work become high spots, as the compressed areas are thinner than the surrounding areas, creating the appearance of a series of reversed dents.
This isn’t sensational; I’ve seen this both in my own work and in the work of other professional shops. We didn’t even have to look far to find bulges caused by PDR on a donor hood after removing the original paint. Of course, I’m sure everyone has their own solutions, but in my opinion, working on a painted panel is more time-consuming than the alternative method I’m considering.
What I do is polish the sheet metal to a mirror finish to reveal any dents and bulges. Then, I perform PDR and, after ensuring the bare metal, not the primed metal, is flat, I apply the primer. I also want to emphasize my fear of shrinkage between different coatings, so we’re extremely careful with our material selection and curing cycles; any misstep could ruin the work.
Highlights
Welding
The several panel replacements needed in the Big Apple would have been enough to send anyone to the junkyard, even 24 years ago, when KBB thought the 1997 S 420 still had a value of $45,000.
The first was replacing the left front fender, which had been damaged in a collision. The original repair was a crude stretching and generous filler application. This part isn’t made of high-strength steel, so a welded replacement is acceptable. We obtained the replacement from a 1998 S 320 donor in California. Fenders on non-North American and non-Motronic vehicles can vary slightly, so a direct replacement is best done using the same part.
The second issue was the right rear end collision. For one thing, the fender was covered in a significant amount of unnecessary filler. Removing it revealed it was simply covering a minor crease that extended to the rear door. This suggests the car had been slightly scraped. Furthermore, the rear end and right side of the trunk lid had been impacted from behind, which is why I considered the right rear fender a total loss.
Sadly, of the five donors we reviewed, only one, a 1993 300 SEL, had a completely original right rear fender, but it had the hole for the reverse assist mechanism. We had to mask it, so the fit wasn’t perfect. I’m glad we repaired the left front first before the right rear, as the right rear was more challenging and noticeable in my opinion. We cut through the area of ​​the two crashes, which is a large piece. Setting the edges against the fuel cap and right rear door frame helped with alignment.
A somewhat amusing change: while I was off for the weekend, our metalsmith took the liberty of welding the fuel fill door bumper support, which was only present on the early cars, onto Big Apple. He thought it was a nice detail, and he was right, it was a part that was later omitted. But in terms of period accuracy, it would have surprised the Pebble Beach judges. I almost grabbed the saw to remove it, but changed my mind at the last minute: let’s leave it here for a test run to see if an expert would notice it. If they do, at least I was honest enough to tell him about the replacement.
Smoothing
As previously mentioned, before starting the sheet metal work, it is crucial to determine which areas need to be smoothed. Aside from the weld seams, the body is dotted with countless small dents that have never been addressed—quite literally, there are hundreds of them.
The strategy is to first polish the metal to achieve a mirror-like reflection, at which point the imperfections in the sheet panel become immediately visible. To achieve the closest possible mirror effect, I began by testing on the right rear door, which had the most dents. As it turned out, this is not a quick job. After testing different tools and abrasives, I decided to use 180-grit, 400-grit, 800-grit, 1200-grit, and 2000-grit sandpaper on a DA sander, without adding any compounds. The coarser the sandpaper, the more detailed and thorough the sanding needs to be, as the coarse scratches will never be removed by finer sandpapers, and the mirror-like finish would be unattainable.
Since each sheet panel requires several hours of sanding, I must also protect the completed panels to prevent rusting. Otherwise, I would have to go back to using coarse sandpaper to remove the rust and repeat the entire process. The panels, polished to a mirror finish, are marked with all visible dents, much like examining bacteria under a microscope—you might feel discomfort or even despair, but in the long run, it’s beneficial. To put it simply, even panels painted with silver paint before sanding can hide a great number of small dents. These sneaky dents sometimes reappear after the paint contracts.
These dents are slowly addressed with PDR (Paintless Dent Repair), a process entrusted to our metal smith. I must admit, once you’ve identified all the issues, you must accept that not all of them can be fixed. Even though the mirror finish helps, some fine dents are almost impossible to touch up. Compromises must be made, but it’s essential to ensure that the dents that can’t be repaired will be filled during the upcoming insurance repairs (primer). Of course, if someone insists on removing the panel to be placed on a English wheel, that is also an option.
Alignment
Panel alignment on this car, with gaps on both the left and right sides no longer pristine, is no easy task. What would I do? This part actually happens simultaneously with welding. If I impatiently weld everything before aligning, it’s too late.
First, alignment should be done from back to front, as the area behind the rear door is not flexible. The order is rear door, front door, front fender, and hood. Since our left front and right rear corners are no longer pristine, we can only use each side as a benchmark. Align the left side first, then align the right side using the same standard to see how much difference the front ends will have. The welding work was handed over to our blacksmith. As a complete layman, I didn’t have much to say about sheet metal cutting and welding, but my advice did make a difference.
Our blacksmith, who is actually our sheet metal worker, painter, and my mentor for many years, is the most proud person you can imagine. Naturally, this seemingly easy task doesn’t scare him; he always laughs at my worried face. After pre-assembling the replacement panels, I suggested installing the fenders and hood to test the “three-way intersection” of the hood, fenders, and lights. After all, it had been crashed, and even if the underbody had been straightened, who could guarantee it wouldn’t be deformed?
At the time, I was still busy stripping the paint off the hood and fenders. He felt that installing these unfinished parts on the car was not only a waste of my time, but also a lack of trust in him. As he put it, “Cutting exactly to the original edges will only result in a 100% match.” Frankly, I agree, but I can only trust my eye. So, after carelessly installing the fenders, a miracle happened. The holes didn’t align, and the fender was about 6 mm off from its intended position!
This was certainly frustrating, but also a lifesaver. After taking measurements in multiple dimensions, we discovered that the car had been squeezed between the front wheel and the front door, and the outer frame that supported the fender was bent. This also made the accident picture clear: the car didn’t appear to have been involved in a collision, but rather a cylindrical shape. I’ll leave the details of the accident reconstruction for later. Anyway, we managed to move the 6 mm missing from the left front corner forward in time. If we discovered this after welding or even painting, it would be a disaster.
To be continued
After completing the gap and flatness checks, the entire car body was once again sanded roughly to enhance the adhesion of the primer and prepare the surface for painting. The AUTOCOLOR P565-985 zinc-rich etching primer was used, which doesn’t require sanding due to its properties, though it was done just in case. The thickness of the primer applied ranged between 10-15 µm, leaving space for the subsequent mid-coat primer, color paint, and clear coat layers. The goal was to control the final film thickness to be between 100-120 µm horizontally, and between 80-100 µm vertically.
This summary actually does not include the roof repairs mentioned earlier. The presence of the sunroof complicates matters slightly. We’ve removed all the filler from the roof, but the roof’s double-layered structure doesn’t allow for proper PDR without compromising structural integrity. Additionally, a dent was found above the left C-pillar, indicating that the car was indeed pressed by something.
Analysis of the Damage and Repair Correlation to Total Loss:
1. Front collision:
A minor front collision, though enough in 2001 to cause a total loss, involved the use of a Japanese hood that would have been difficult for American repair shops to source. It’s more likely that the repair was carried out in Southern China, where Japanese parts are more commonly used. Considering that the car received a rebuilt title in 2002 in New York, the collision likely occurred after the car was exported from the U.S. to China.
2. Right rear collision:
The damage here consists of a scrape from the right rear door and a light rear-end collision at the right corner. The extent of the damage in 2001 was not severe enough to cause a total loss. A considerable amount of filler was used in the repair, but it has not cracked. If this repair was done in the U.S. in 2002, these fillers wouldn’t have lasted this long. Moreover, the right side has only been repainted once, indicating that the collision likely occurred not long ago, possibly in China.
3. Combined damage:
After discussion, the remaining three marks appear to stem from a single incident. The first is an indentation on the left front fender, which wasn’t caused by a collision, but rather by a cylindrical object pressing down on the fender from above, causing the structure to cave inward to the right. The second is a dent at the front of the sunroof, and the third is a dent on the C-pillar. It seems that a roadside object, possibly a street sign, fell beside the left front fender, pressing into the fender and impacting the roof and C-pillar.
Considering the total loss event and the vehicle’s range of movement, the third group of damages could very well be linked to the 9/11 terrorist attacks.