Zed Primed Again

I get that this is becoming almost comical in how cyclical the priming on Zed (1979 280ZX) has been. Today's post is another "Priming the 280ZX" posting. As much as I would like to say it is the last, I know there is one more primer shooting day coming, when the body kit arrives.

I did this work around another heat wave here in the Pacific NorthWest with temps pushing 40*C (104*F) at the peak. I spread out the final prep work over the full day Saturday and shot the primer Sunday morning. All of the other final sanding was after work in the heat of the day the week prior, causing me to literally pour sweat. Anyway, off we go.

Why More Primer

First, the obvious question... why more primer? For starters, this shoot was black 2k primer intended as the final coat of pre-paint. Hi-build primer can absolutely be your last coat of primer. In the reading I have done, many people have had great success with shooting their base/color coat(s) on top of the hi-build. I decided that I wanted a harder shell underneath the base than the hi-build provided. Also, the primer immediately under the paint is what is exposed when you get a rock chip. I think the light grey would show more than the black. Consider too, the color of your primer has a subtle impact on the color of your base coat, unless you put extra coats of color on to cover that. I felt that the black undertone beneath the gun-metal grey would darken the grey. Last, through the final rounds of Bondo, I sanded through to bare metal in a few spots. Those, at least, needed priming.

Preparation is Key

If you have read any of the posts about my efforts on Zed, this section is probably moot. Still, it is worth underscoring the importance of getting the panels as flat and straight as you can before you start spraying. Why? Because the paint is a very thin film of color laying on top of whatever your body shape is underneath. So, if it is lumpy, bumpy, or even deep scratched, it will show through. I performed many rounds of Bondo application and sanding, each time getting a little better at it, and each time getting the panels that little bit nicer. My final process has proven effective: mix a small batch (250ml / a US cup or so), applying slightly too much Bondo to the imperfection area on one pass (and don't touch it once it's applied), sand with less coarse paper (150 grit) for shaping and 400 for smoothing, and last, circle issues for further repair with chalk. This worked for me, and would probably work for others. The higher grit number means you use more paper and it takes longer to get the shape. I hand-block rather than use a DA orbital sander, which is additionally slower. I found this to be a fair price to avoid over-sanding.

Once sanded and smooth, the dust needs to be removed. Pigpen, my shop vacuum, is relatively effective at removing dust. The dust is so fine and Pigpen is so old that dust finds its way around the filter, creating a small cloud of dust around the canister (hence his new name of Pigpen, from Peanuts). I followed the vacuum with blowing compressed air on the panels (after the dust cloud passes) and then I set up for shooting. Since this shoot included the insides of the hood, tailgate and doors, there was considerably more prep than the last few cycles. I repaired the masking at this point as well.

For this spray session, I also prepared the hinges. I started with spray cleansers, but found they were not efficient with the 40 years of grease embedded in the hinge works. So, I grabbed a bucket, tossed in a dishwasher detergent pod and dropped the parts on top. I filled the bucket with a garden hose and then moved the parts around with a pry bar. I let the parts sit for an hour or so, agitating the bucket or moving the parts with the prybar periodically. I drained the dark grey wash water and rinsed the parts with the hose. All of the grease was completely gone.

Set Up

With the panels off the car, I need a wide area to shoot everything. I use a second carport space, laying a big blue tarp down as a floor. This keeps the dust away and protects the driveway. Onto the tarp, I arrange the panels to I can easily move from one to the other without drooping my air hose onto wet paint nor creating a weird maze to navigate while trying to spray. Once arranged, I blew off the panels again with compressed air and then cleaned the panels with oil/grease cleaner (Oil Eater). I do one last check, by holding the air hose and walking the area, making sure I can get to everything.

I have gotten relatively quick at getting the gun ready now. The 2k primer is a 4:1 mix. So, for a 20oz ($20US<) Harbor Freight purple gun that means 16oz:4oz of paint to reducer. I pulled a clean pickle jar out of my glass recycling to use as a mix jar. With a measuring cup and water from the kitchen, I marked a 16oz line and a 20oz line on the jar. My process was to pour in 16oz of primer to the first line and then add reducer to the upper line. A quick mix, and pour into the gun and I was ready to go. Doing it this way gave the air compressor time to catch up to me.

The Shoot

I checked my spray fan against some of the masked off glass, as well as the underside of the hood (it was flipped upside down so I could shoot that side first). With a decent fan, I started shooting around the radiator support first. I figured if there were any mishaps, better they happen in an area that will be almost completely hidden from view later. There were no real issues. I had a few "tiger stripes" where the gun would sporadically not produce a paint fan... resulting in what looks like a tiger stripe. I believe this could be attributed to either too much air pressure or a crappy gun. I will recalibrate for the next shoot. Overall, though, the primer laid down very well. Once all of the undersides were done, I sprayed out the rest of that batch and flipped the doors, hood and tailgate over. Then, I shot them. One thing I did this time was take advantage of the 1/2 squeeze on the trigger to blow air: If you press the trigger halfway, compressed air comes out, but the opening isn't big enough to pull paint. So, I was able to quick-blow the panel immediately before spraying. This trick will be more useful with the color, but it was good to practice it.

After I was done, and the primer all dry, I looked back over the spots where there were significant Bondo sections (again, not thick, just a wide area) and they look very good. Even the middle of the hood, where all eyes will be most of the time, the center ridgeline is exactly centered and looks just as I intended.

The pictures on the right show the before and after of the passenger rear quarter panel. I think they show how careful work can produce some pretty great results. I really like the satin glow. It shows the body contours very well, allowing me to look for remaining imperfections fairly easily when compared to the hi-build which sat flat. Everything looks pretty amazing to me, and I do not intend to pursue any additional rounds of Bondo on these panels nor the main shell. That is a huge milestone.

Next Step Musings

I am still waiting for the arrival of the body kit that I ordered in June. This is not a supply chain issue, really, it is about a manufacturer getting their business back operational after a CoViD shut down. I understand that my kit has been produced and is in transit. Depending on timing, I may 400-grit sand what I just shot and then plan for base coating the areas which are going to be either under the kit or under other body panels (like, maybe paint the front supports for the fenders, for example). I know I want to do those on a different day than the rest of the body, but I don't know how far ahead I want to get without the body kit in-hand. I understand that these kits are really one-size-fits-none-perfectly. So, there will probably be some shaping at least. Regardless, these kits need to be minimally surface sanded to remove the gel coat for paint to adhere. Last, I have read some advice about leaving newly formed fiberglass panels in the sun for a week so they get nice and warm help to complete their off-gassing / curing. Apparently, they will behave better over the long term if this is done. I recognize it sounds a little odd, but this came from someone who does these body kits all the time, so I'll trust it. If the kit arrives soon, I should still have time to finish the prep and paint before the weather turns... assuming the weather stays warm/dry until the middle of October like it usually does/used to. If necessary, I will switch it up and paint everything I can, leaving the body kit for next year.

Anyway, that's it for today. Thanks, as always, for following along--