Preparing an Aftermarket Bed for Paint

By “Rotten” Rodney Bauman   –   Images by the Author

In anybody’s paint shop, being the painter comes with its pressures. Here in our own shop, for example, our subject 1955 Chevy second-series project’s finish had better look good—and it had better endure the elements well, as well.

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Still in their boxes, we can tell they’re beautiful. Near the upper stake pockets we find small, uniform creases. We’ll iron them out with a little bit of filler once the new panels are thoroughly cleaned and sanded.

Assuming you’ve been with us, you know that we’re taking advantage of available aftermarket sheetmetal. It’s nice to have the option. In this instance it’s quite necessary, but as the painter here, I must wonder if faraway factory workers truly give a hoot about the work that I must do. Perhaps they do, but since I can’t be absolutely sure, I’m somewhat reluctant to trust whatever coating a brand-new panel might arrive with.

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Here’s a look at solvent-borne grease ’n’ wax remover, disposable toweling, household cleaning products, green scuff pads for initial scouring, and so on. It’d sure be nice to use the big steam cleaner … but we’ve already talked about that.

As we’ve understood, reproduction panel manufacturers sometimes use a black “paintable” Electro-Deposit primer coating, or “E-coat” as it’s commonly called. The familiar black E-coat can be prepped and recoated at the painter’s own discretion. Some painters work with it, while others strip it away for a fresher start and proper peace of mind.

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First things first, let’s get after the oily residue with solvent-borne grease ’n’ wax remover. Before it evaporates, we’ll wipe it dry. When we’re done, we’ll do it again.

During the course of our ongoing build we’ve used a number of black E-coated body parts. Our left door, however, came with a questionable silver coating. It failed the solvent test. Oddly, the wimpy silver stuff had a black coating beneath it, but we opted to strip that door to bare steel.

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For tough-to-reach crooks and nannies, like stake pockets, we’ve fashioned a specific-purpose tool. It’s oily in there, too, so this’ll continue on and on, as well.

Currently, with the little truck’s cab, doors, and frontal sheetmetal painted, cut, and buffed, it’s finally time to address a brand-new short Stepside bed. Yes indeed, it’s all the same stuff that I went and picked up a while or two back from Premier Street Rod.

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This is our second lap with solvent-borne grease ’n’ wax remover. Here on clean disposable toweling we still see oily residue. With lunches packed, let’s take it outside.

Having now been dry-fit assembled once already, the bed is back in pieces for paintwork. Coming up, we’ll attempt to illustrate a dramatically different procedure. This won’t be anything like the new panel prep methods we’ve previously touched upon.

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One lap into our outdoor degreasing marathon, the panels are scoured down with scouring powder. For the rinse cycle, however, our hot water could be hotter.

The new bed panels are galvanized with zinc plating. Also, from the stamping process there’s oily residue left behind, which won’t be easily rinsed, scrubbed, or scoured from within crooks and nannies—particularly those of the bedsides’ stake pockets.

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By the time our hot water travels across 25-foot concrete, it’s delivered warm at best. So, we’ve jacketed our hose with pipe insulation. For the second lap this made quite a difference and our expendable pressure washer survived!

On the upside, we’re not totally on our own to figure out the special prep required for brand-new bed panels. Their manufacturer (Mar-K) does provide instructions for the job. It’s really pretty straightforward stuff that a good painter should already know. Speaking of good painters, it’s nice to know others to confer with on occasion.

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Dried off and blown out, the new panels are back in the body stall, and they’ve been cleaned again with solvent-borne grease ’n’ wax remover. Now with ordinary H2O this is the test. If it beads up anywhere, we’ll repeat the previous steps. So far, so good.

Since this’ll be my own first time working with a brand-new galvanized pickup bed in pieces, I’d kind of like to confer with an expert on the subject. In the paint department of Premier, Isaac Wilde works with these types of bed panels routinely, so, we’ll confer from time to time as we go.

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Trying not to sand through the zinc plating, we begin with the flatter expanses. Here a 6-inch DA (dual-action) sander gets its part of the job done. We’re using 120-grit abrasives, but 150 or 180 would work just fine, as well.

Also, as we go, we won’t try to make any of this look easy. Whether we like it or not, a new bed’s paintwork begins as pure drudgery. For best results, expect to use chemical cleaners repeatedly before switching to household cleaning products, and steaming-hot water to rinse away the oil.

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Eons ago, when I first saw this type of detail sander at a big tradeshow, I knew I had to have one. I didn’t know how rarely I’d actually use it, but here it’s real handy in corners where the DA couldn’t reach.

Right about now it’d sure be nice if I hadn’t parked our big steam cleaner in an enclosed car trailer for winter storage. Come to find out, there’s always water remaining inside the pump. Sure enough, when that water froze, it wrecked the pump, and oh my goodness, a replacement pump is spendy!

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The same detail sander is also the hot tip for the tailgate—at least in the tough-to-reach corners of its characters.

So, where we happen to be, we get a few painter-friendly months per year. At the time of this typewriting it’s springtime, and there’s no time for downtime. To keep our priority job moving along, our big steam cleaner’s repairs must wait, but we’ll still need steaming-hot water. Our shop’s water heater is a real hot rod. A garden hose could be connected at the washing machine. What if we try hot water through our little cold water pressure washer? We’ve read the entire operator’s manual, and nowhere in there does it say we shouldn’t.

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With 80-grit glass beads our handy little spot blaster cleans out stitch weld irregularities. It’d do a fine job on spot welds, too, but with so many spot welds, it could get messy.

As a disclaimer, we’re not exactly suggesting that anyone should try this at home. So far, we don’t know what hot water will do to our own little cold water pressure washer. We do know, however, that oily residue removal is imperative for good results in the paint shop. In this instance grease ’n’ wax remover isn’t enough on its own. For the soapy steps, steaming-hot water at a fair pressure is a must, even if our little cold water pressure washer must croak for the cause.

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As a tidier alternative, a spinning wire-type implement works well for spot welds. This one’s got the right shape, and it’s stiff enough to leave a little tooth for primer adhesion.

Initial cleanup of our new bed panels will begin with solvent-borne grease ’n’ wax remover. Before that evaporates, we’ll wipe the panels dry with clean disposable toweling and repeat as necessary.

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For the areas machinery won’t reach, we end up sanding by hand. From here we’ll roll all four panels over on their fixtures and repeat the entire procedure.

Next, for the outdoor steam-cleaning marathon I’ll have my hands full enough without moving a tripod around, and really, I’d rather not spatter a perfectly good camera with hot, soapy water. To illustrate that bit of action I could draw stick figures later, or perhaps I’ll ask Mrs. Rotten to snap phone photos from a safe distance away.

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Once the new bed panels are thoroughly sanded, it’s filler time, but only for the small creases we pointed out earlier in photo number 1. Here we use different fillers for different purposes. Over zinc plating, Z-Grip fits the bill.

While outdoors, we’ll have two go-rounds with scuff pads, scouring powder, and lots of steaming-hot water. Then we plan to repeat those steps (also twice) with leading-brand dish detergent, which, by the way, does not contain animal-derived ingredients.

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When it comes to body shop staples, we pretty much get what we pay for. From our local parts purveyor, Z-Grip isn’t cheap. We generally purchase ours from Summit Racing.

When the new panels do eventually make it to the body stall, they’ll be set up at a comfortable working height where they’ll be cleaned with solvent-borne grease ’n’ wax remover and clean disposable toweling—again, before tedious sanding and minor bodywork begin. In this instance, overkill is good, and it sure beats fisheyes later in the booth.

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Also from Summit, this little Motor Guard sanding block has curled with use over time, which is helpful right here. Switching to finer grits as we go, we’re finishing with 120.

So, on that note, shall we get on with the step-by-step stuff? Along the way we’ll cover proper sanding for clean, galvanized panels, materials to some degree, and the order in which these steps should be taken.

Check out this story in our digital edition here.

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Now we have sanded panels in their primetime positions. We haven’t touched them with bare hands, but here we go again with solvent-borne grease ’n’ wax remover.
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This time the black stuff isn’t oil. If we’d sanded bare steel we might assume it’s just carbon, but chances are, this is zinc. At any rate, we’ll do this at least once more.
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By this time we’ve applied two coats of black epoxy primer, which hides nothing. These bedsides are nice! We won’t, but we could almost skip straight to base color.
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We’re looking hard for fisheyes, but no, we’ve won the war on oily contamination. By the way, this tailgate, straight from the box, is just as nice as the bedsides.
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Yes, we’re squirting some urethane primer-surfacer, but only in two small spots where we’ve done a bit of welding on the opposite side.
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Back in photo 1, the small, uniform creases sure enough turned out to be the only bodywork required. We’ll guidecoat and block those primed areas the usual way.
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For the new bedsides’ larger expanses, final paint prep won’t be bad. We’ll do some sanding and finish with a gray scuff pad before epoxy sealer, base color, and clear.
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