Bondo Zed

Today, we return to Zed, the 1979 Datsun 280ZX. Earlier, I completed the paint removal that C started. With the smoke finally gone, and the rain storm that followed passed as well, I could start with the body filler so we can get this car painted. I admit that the 2 weeks of smoke gave me time to consider whether I wanted to have a body shop do this or not. I decided that I wanted to learn, and even if I did it poorly, I would learn. I could always farm it out later.

Seek and Mark

The process of finding imperfections to resolve with body filler (Bondo, bog, putty) reminded me of my old house painting days. With a light in-hand, shining on the subject, look for dings. When painting a house, you do this with some spackle in-hand, and just fix the issue right there. Or, if this is after priming, you do it with putty and, again, fix it right there. In both cases, you fix as you go. With a material like body filler, though, that doesn't work. Bondo is pre-mixed with a hardener so while you are out looking for the next ding, it is drying out. So, instead, you walk the car with a pen or piece of chalk. As you find spots, you mark them, either drawing a circle around it or otherwise drawing on it to attract your attention as you circle with the steadily-drying putty.

Hammer Thoughts

Zed mid-filler

By now, most of the worst spots have been hammered out, leaving some hammer marks or imperfections that you just couldn't get to, or couldn't get perfect. Between this crappy economy and buying T's A4, my resources are gone, so I did not buy a set of body hammers. At some point, if I find that I am enjoying body work, I will get a set of these Covell hammers, but $300US is a bit much for a one-time set of hammers. Big thanks to the HotRod Hippie (check his youtube channel here) for the hammer reviews to help me find a set that is good enough for quality work (not HF hammers) but won't break the bank like SnapOn. 

So, after many weeks of using standard tools, like a framing hammer, a rubber mallet and assorted screwdrivers, a pry bar, etc, I have the fenders and doors as close to straight as I can get them. Most important, the remaining dings are slight, like less than 1/8" off-straight/flat. These areas were easy to find. Even while I was marking spots, I decided to try some more tuning on the passenger door handle area that still looked a little too deep for filler.

Mix a Batch

No, not in the Letterkenny way. I mean make some body-filler. The instructions are on the can, but after messing with the stuff for a few days, I concluded that less hardener is better. This gave me more time to work with the material before it started to set up. For a work area, I grabbed a small steel table that we inherited from the Eugene house. Atop that table, I set a 12" x 20" piece of glass that we also found there. I used the glass sheet as my body filler mix-and-apply-from surface. This saved me the $8 for a steel sheet at Harbor Freight, but it also comes clean easier: Just scrape the surface with a razor blade after the material turns to rubber, and it's ready for another go. Last bit of advice: no matter how you may feel about wearing the blue gloves when you work on your car, I strongly suggest wearing them for mixing and applying body filler. Getting it off your hands afterwards took me 4 rounds with the GoJo. The next round with the filler, I wore gloves. No muss, no fuss.

Apply

more Zed mid-filler

Before I chose tools, I hit the interweb for opinions on the various applicators. There are basically 2 kinds: plastic and metal, and there is, of course, a religion about these. I got the plastic ones because they were cheaper. These don't have a handle, which means your fingers are in the stew, but that also means you are that much closer to the work, allowing you to bend the applicator to contour. I'm sure the steel applicator folks have a solution for this as well. Your car, your choice.

Once I started applying, I went the route of too-little-is-better-than-too-much. I did not want to spend all day sanding a bunch of extra filler. I got my wish, but I failed to recognize just how much the filler shrinks when it dries. This oversight drove me to apply-sand-reapply 4 rounds before I had all of the spots filled well. Of course, many of the small spots were completed in one shot; I had to return to areas which had multiple dings or an inward sag that needed to get built up. Again, none of the areas needed more than 1/8" of material thick, but some areas, like on the fenders, had a lot of little dings that took some effort. Mostly, this was a learn-as-I-go thing. I think I tried to spread the material too thin, or far beyond the edge of where the damage was. As a result, I needed to re-apply because I simply went too thin.. on the same area... multiple times. Learning is fun, but my arms we so sore from sanding all day.

Sand

Yeah, the sanding is the effort part. Most folks recommend using 80-grit sandpaper. I had a limited amount of that, so I used 60-grit. This accelerated the initial cut-down, and by the time the filler area was approaching flat, it had worn down to less than 80-grit. It was probably more like 100 by then. I used a full-size (8") sanding block the entire time. Keep the block even with the contour of the body panel you are working on. So, for example, the fender on Zed is flat running front to back, so I held the sanding block parallel to the ground. Then, sand in a diagonal pattern, mixing it up so you're sanding in an "X" shape. I did a little sanding in a circular motion, as well as top-to-bottom, but the best, flattest, smoothest results came when I did it diagonally. Also, try to keep up to half the sander on the body panel if you are not sure how it contours. This held my sander from over-sanding, once I figured this out. My over-sanding caused some extra batch-work too. More cost of learning.

Wash Rinse Repeat

As you sand, you will eventually arrive at a flat, smooth area adjacent to the undamaged body panel. Congrats. You may find, however, some spots that the sander missed, but was sanded all around it. That's a low-spot that needs more filler, and it probably happened because the filler shrank on you. Or you simply under-applied. No worries; just mix another small batch and fill it in. I suggest you learn from my mistake, and fill it with a little extra on top of it. This is how you properly use spackle too, but it took me many times around to figure out what was going wrong,  and I still did it.

Anyway, put a little convex material where the un-sanded spot was, and have a thin layer on top of what was sanded. If you don't, you run the risk of over-sanding those spots and you won't be flat and level with the surrounding body. Yep, I did that too. There is also the risk of putting too much product on, creating a false body contour, leaving you a bunch of extra sanding to get the panel back to the correct line. What I mean by this is you can over-apply, sand it smooth and leave you thinking that you got it right. Then, you get right on top of it to confirm the panel and realize that the body panel isn't following the original line anymore. You gotta sand all that off and do it again. Yes, I did this as well.

Well, that's it for today. Once I am 100% satisfied that the body is as correct as I can get it, I will be vacuuming and blowing it out, removing all the dust I can. Then, I will start masking for primer. I ordered some high-fill primer from Eastwood so that should fill in the tiny imperfections. But, I'm getting ahead of myself. First, I need to close-inspect Zed, possibly body-fill some more, probably sand the untouched metal with some 400, then clean, then mask.... yep, lots left to do and we are already in the first full week of Fall. Still hoping to have him painted before the rains have fully arrived. Based on the weather this past week, that window may have already closed.

Thanks, as always, for following along. Please accept that CoViD-19 is still a genuine threat (back to 40k+ new cases per week in the US) and that wearing a mask is one small way you can help contain it's spread. It is not a commentary on freedom, it is a commentary on being a responsible citizen.