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Tour Car Bodywork
Tour Car Bodywork Continues
Mar 17, 2005
Dale Etheredge Auto & Performance
Covington, GA 30016
METAL FINISH U.S.A. (Division of H&H Autobody, Inc.)
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Tour Car Bodywork
Though we showed the trunk floor mostly in place last month, you'll find another critical area located on either side of the actual floor area. The left and right trunk floor extensions seal (or finish off) the inner wheel housings and lower rear quarter panels, so that no moisture can enter the trunk area from the rear wheels.
Proper fitment and grinding (or cleaning) of the mating surfaces is extremely important here.
No matter what kind of part you're installing, trial fitment will make the overall job much closer to perfect. With the trunk floor extensions, your front (to-wheel-housing area) fit and alignment needs to be just right...
...as does the inner, lower, and rear-most mating surfaces of the new extension panel.
Not to beat a dead horse here, but your front flanges need the most careful evaluation, as that's where your trunk floor extension meets the inner wheel house.
The trunk floor itself received a nice continuous bead. These welds will be ground smooth for cosmetic purposes. However, grinding (or dressing) your welds will also help you locate any gaps, which can be fixed easily with a few more zaps of the welder.
The inner construction for your back panel helps tie everything together on the tail end of things. Alignment is really critical here, as are good sturdy welds.
In another part of the shop, work was beginning on the new Goodmark front sheetmetal panels. Here, the new front wheelhousing is being bolted to the fender, prior to trial fitting on the car.
A while later, the DA (dual-action) sander came to life, spinning an adhesive-backed sandpaper disc to remove the factory primer. Like with many orbital tools, DAs are used with quick strokes across the surface, to reduce the amount of heat build-up in the panel.
Though more DA sanding remains, the front sheetmetal was trial fitted, checking for alignment, proper gaps, etc. You'll note that even the grille and lower valance panel are bolted up. This is better done before paint, in case shimming, and/or fitment issues arise.
The steady buzz of the DA continued filling the shop. While this factory primer is used basically for panel protection before you purchase it, scuffing can be done with either 220- or 320-grit paper.
With door skin installations, your first critical steps come in removing the old panels. Special tools are available that "peel" the outer skin from its inner construction. The entire perimeter of the skin itself is merely "folded" around the inner construction's mating flange, then, hammer and dollied flush. The dolly is worked on the outside of the panel, while your hammer strokes land on the inner frame.
Notice the smooth and flat edges, with no visible "dimples" from the hammer and dolly work. That's the right way to install a door skin. You can also see just how flat and smooth Goodmark's panels are. Great pains are taken with the tooling that strikes each panel, as well as the way each item is packaged for secure shipping. There's nothing worse than buying a new piece of sheetmetal, only to find that it needs body work right off the bat (!).
A "guide coat" of light-colored primer allows a body man to better verify panel alignment and overall fit. Dark-colored primer makes it more difficult to pick up high and low spots, and body line consistency.
Our body specialists at Metal Finish U.S.A. continued by hanging the door assembly and bolting the hood on. The more you put a car together and pull it apart, the better you'll get your gaps and character lines to appear. Spending the extra time here will pay dividends, if you plan to have car show judges review your work.
Shown here is a panel flange punch, used to make a series of holes for a better weld to the respective mating surfaces.
A standard drill is used to make a neat row of holes in the B-pillar, or lock post area. Note: The large hole in the panel is for your lock post vent. When your door is slammed against the weatherstripping, and the window is in the up position, the pressure created has to be vented somewhere, otherwise, you'd have to roll the window down slightly to let the pressure escape.
Here's where quarter panel fitment comes into play.
B-pillar fitment is critical, as each piece of inner construction must be aligned properly, otherwise, the panel would never fit correctly.
When each mating surface is securely located, it's time to clamp your new piece of sheetmetal in place.
The passenger-side quarter panel came next.
A few strikes of the "gentle adjusting hammer" were necessary in the upper lock post area. Notice how smooth and flat the metal is, and also, the neat row of holes to be welded securely to the inner wheelhouse.
Next, the back panel is fitted in place, with careful alignment to each rear quarter. Don't forget, if this step is misaligned, it'll throw off your quarter(s) and most likely, your deck lid alignment.
With the back panel aligned and fitted, it's clamped in place, and then it was time to crank up the welder.
The job continued, welding the wheel opening to the inner wheel house.
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