Crown Victoria Project Update - Build a Panther, Part Three: The Paintjob

Often, the dilemma when contemplating a paintjob is whether to strip the old paint or just scuff it before spraying the new stuff. I did a combination of the two. This car was wearing its original paint, black with a white roof and white front doors, but the white paint was peeling off. I've heard from some cops that they have the same problem—the factory white is especially susceptible to sun damage. I scraped all the loose white paint off the roof with a razor blade.

The light bar had been secured to the roof with sheetmetal screws behind the weatherstripping just above the B-pillar. I welded the holes closed using our TIG welder, rather than a MIG because it generates fewer sparks.

Even so, if you weld anywhere near a car's interior, keep a fire extinguisher close and be absolutely sure that any sparks that may have fallen inside the car are completely cooled. We've heard horror stories of cars burning to the ground because a stray spark dropped somewhere deep in the bowels of an interior panel where things like insulation and sound deadening material can smolder for a while before erupting into a towering inferno. I ran a bunch of compressed air through each hole and avoided singeing my headliner, but in hindsight, it would have been safer to remove it prior to welding.

I figured painting just the roof first would be a good test of my ability to spray a decent black paintjob. Here is the roof stripped of all the loose paint, leaving behind the still-good factory primer. The remaining white areas were where the paint was shielded from the sun under the light bar and under the car's number decals. This was a cool find because Santa Barbara County had removed these roof numbers before sending the car to auction. Judging by the shapes, mine was car 418. This remaining paint still had a strong bond to the primer, so there was no need to sand it all off. Just be sure to sand the transition between the primer and the paint. This technique is known as featheredge sanding and it removes the ridge between the primer and the paint on top of it. To do this, I used 220-grit on a DA followed by 400 on a sanding block, sanding until I could no longer feel a difference between where the paint stopped and started. Once masked, blow the surface with compressed air and wipe with degreaser.

Epoxy primer is a good general-purpose primer. It can be applied to bare metal and, unlike a surface primer, it resists moisture once it's cured. This is beneficial if you don't have time to spray the topcoat right away; you can leave your car outside in epoxy primer and it won't absorb water if it gets wet. Usually epoxy primers are available in light grey, neutral grey, and dark grey. Obviously, it's best to use a light primer if your topcoat is a light color.

When spraying something tall and relatively flat, it's good to make (or buy) a platform that allows you to move the length of the surface. Standing on a ladder like this, your passes with the gun become arc-shaped, especially toward the center of the roof. This can cause thin, uneven coverage—not so critical for primer, but bad for the topcoat.

To keep the costs down, I used a single-stage acrylic urethane rather than a more expensive basecoat/clearcoat paintjob. To do the roof, I tried a couple of different brands, one from one of those “supercheapcarpaintsforonedollar” online stores on the roof itself, and this Valspar enamel on the driprail moldings.

Charitably speaking, the results were less than optimal. The glitterlike effect on the roof is actually solvent pop. Imagine if you could flash-freeze a glass of Coke, suspending the bubbles of fizz in place as they rise from the bottom of the glass. The effect is similar here; the paint cured as the solvents used to thin the paint were still evaporating out. Usually this is an indicator of an improper mix ratio or using too fast an activator. The Valspar paint on the driprail moldings (the L-shaped pieces between the roof/back window and the quarter-panel) came out better, which was interesting because I sprayed them at the same time and with the same gun settings as the roof. To be fair, the roof paint was nearly a year old, and I had to thin it out more than the recommended amount just to get it to flow through the gun, but the Valspar paint was not quite as old. Paint and its additives definitely have shelf lives.

After my experiment with the roof, I got to work in earnest on the rest of the car, stripping away the aerosol-black on the doors and block-sanding the entire body with 150- and 220-grit sandpaper on our Durablock sanding blocks (seen in the grille opening). I originally planned to tape off the window trim and door handles but ultimately decided to remove all the window trim, door glass, window felts, door handles bumper covers and exterior lamps. That was extra work, but the finished job looks more professional as a result. The window trim, glass, and door handles are all secured by rivets. Make sure you've got a drill sharpener.

Block-sanding the paint quickly reveals any imperfections in the sheetmetal. As stated earlier, the body was in good shape, with only a few small dents in the decklid and quarter-panel likely caused during the cuffing and stuffing of a few perps. I was able to straighten these out with a slapper hammer and dolly.

The dolly is doing most of the work on the backside of the dent. Push hard on the dolly while lightly hitting around the crater with the slapper to shock the metal back into shape. A regular body hammer would work OK here, but I prefer the slapper because it spreads the impact force over a larger area.

Check your progress by running a long sanding block across the repair. The low spot has diminished, but I uncovered the high spot that was created when the dent was formed. By concentrating your hammer strikes on the high spot, while still pushing out with the dolly, you can move the metal from the high spot back to the low spot.

The dent is fixed when the sanding marks are uniform across the repair area. This is a good way to visually check your work. While it's easy to feel high and low spots in sheetmetal, very small irregularities can be tough to read by touch. That's why guys spray a guidecoat over primer before block-sanding it. When the guidecoat sands off evenly, you know the panel is straight.

Newer cars have flush-mount glass but finished with a metal-backed rubber channel. I tried to peel this out, but the backing started to deform and I didn't want to have to replace it if it broke. However, you can't just mask this channel off, as it will leave a hard tape line at the transition between the channel and the roof. 3M sells the solution to this problem—trim tape. The exposed blue section is a semirigid plastic that you feed under the rubber trim.

With the tape in place, peel off the backing to expose the adhesive and fold the tape over tightly, in this case, folding it forward onto the windshield.

Folding the tape forward pulls the plastic edge up, pulling the rubber trim away from the panel, which opens just enough of a gap to spray paint behind it. When you pull the tape off, your new paintjob will extend past the trim and look factory correct.

Masking a car is a huge job. I decided to tape off the door openings so I could keep the doors opened and blend in the door jambs. Here is the car just before I began spraying. Again, thoroughly blow the car with compressed air and wipe it with a wax and grease remover. Tech tip: masking tape does not stick to tires. I tried to tape that painter's plastic to the tires, but the tape came undone several times throughout the job and once blew the plastic into my paint. Fortunately, it stuck to the inside of the wheel lip and didn't leave any external marks. It would have been better to cover the tires with something heavier like old towels (watch out for lint, though), moving blankets, or a set of canvas wheel masks to look like a real pro. Or you could just paint the car with crap wheels and tires on it.

This is Valspar's Direct To Metal 2000 series tintable primer. It's the same stuff we used to paint Editor Glad's El Guapo El Camino in the Dec. '08 issue. We had good luck with it then, so I bought another gallon from Top Guns in Gardena, asking them to tint it as dark as possible. The mix ratio is 4:1:1 (primer, reducer, activator), and I sprayed two coats with our DeVilbiss Starting Line gun using a 1.8mm tip. You can topcoat over this primer after 30 minutes of cure time, but if it sits longer than 24 hours, you need to sand it prior to topcoating.

I painted the car a couple of days later with three coats of Nason Ful-Thane single-stage urethane, again using our DeVilbiss Starting Line spray gun with a 1.4mm tip. The paint was a generic black mixed by Meza Autobody supply, also in Gardena, and was mixed 8:2:1 with 441-21 medium- temperature reducer and 483-15 activator. Though I used only a gallon of primer on the car, it took almost two full gallons of paint to cover it. Another reason to spray a test panel—you can gauge how much material it will take to complete the job.

I painted the bumpers separately from the car. Though you can mix flex additives into the paint before spraying flexible parts like these, modern paint is already pretty flexible, so I skipped it. They have held up fine since then. For extra fun, see the Apr. '09 issue on how to repair plastic bumpers.

Tech tip: Support plastic bumper covers fully across their widest part to prevent them from bending. If the paint dries with a weird bend in it, it could crack when you put it back on the car. Also, check that the material you're coating them with is compatible with the type of plastic you're working with. Some bumpers need a specific primer, otherwise the two will react.

My paintjob was less than stellar for two reasons, and both of them were my fault. First, sand scratches were visible through the paint; second, the finish had a lot of orange peel. I put the scratches in there when I sanded the primer prior to painting the car by attacking it with 400-grit dry paper. My belief was that 400-grit would give the topcoat more tooth to stick to. But this primer does not sand well and it clogged the paper. Dragging the clogs across the surface left gouges in the primer. Again, this was my fault, not the primer's. According to Valspar's instructions, if it is mixed with more reducer, it acts like a smooth-sanding filler primer. But mixed with less reducer, it acts like a sealer, giving it a harder surface that does not sand easily. What I should have done initially was scuff the primer with a Scotch-Brite pad—not 400-grit dry sandpaper—then painted it. However, once the damage from the 400- grit was done, I should have wet-sanded the car (because wet-sanding prevents clogging).

Orange peel was my second problem. It is caused by several factors: too much air pressure, holding the gun too far from the surface, under-reduced paint, or using the wrong temperature reducer. Because I used the correct reducer, I can't use that as an excuse. In hindsight, I probably didn't reduce the paint enough. The fix for both the orange peel and the sand scratches was to wet-sand the car, and this is what you need for that job.

3M recommends soaking the paper for about 10 minutes prior to using it. This makes the paper more flexible so you don't have a sharp edge when you fold it.

Use a flexible sanding block and fold the sandpaper around it. The block will apply even pressure to your car's various bends and creases. Keep the surface wet, too. This prevents the paper from clogging. I'm using a spray bottle filled with water and a small amount of car-wash soap to make the surface a little more slippery. Start with 1,000-grit and work down to 2,000-grit. As with block-sanding, when the surface is uniformly dull, you are finished.

You'll have to buff the paint to make it shiny again, and here's what you need. The white pad is more aggressive and is used with rubbing compound. Use the black pad and polish to remove the swirl marks left by the compound. You can wax the paint at this point and be done with it, but I added an extra application of glaze before wax. Tech tip: you can apply the swirl-free polish with a low-speed random orbital machine. Rubbing compound must be applied with a high-speed buffer, though. Put some tape on body lines and panel edges—it's easiest to burn through the paint there. After buffing, remove the tape and apply rubbing compound by hand on those areas.

Buff one panel at a time, working your way around the car. Here you can see the finished door next to the unbuffed quarter-panel. Also note the masking tape on the edge of the quarter-panel to keep from burning through the paint in this area. For extra safety, I propped open the doors with a roll of tape so there was no chance of the buffer touching the panel next to them.

Nearly all the sand scratches and orange peel were fixed during the wet-sanding and buffing process, but it took me two days to do all that work. Here is the car going back together.

Two years later and the car still looks pretty good. However, if I were to do it over again, I'd use a basecoat/clearcoat system. This paint scratches very easily and I constantly have to polish it to keep it shiny.