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Major Surgery Part 2Prepping the new panel and the old body for a perfect fit From the November, 2010 issue of Mopar Muscle By Mark Ehlen Photography by Mark Ehlen
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Here's where we left off last... Here's where we left off last month. The old quarter-panel has beenremoved, leaving the upper body line, doorjamb, and side-marker lightopenings. Last month we explained how to properly remove a quarter-panel so thatas much of the original factory look as possible could be preserved. Infact, when this work is done correctly, no one should be able to tellthat the quarter was ever replaced. No telltale scars should show. Notonly that, but the new panel should survive at least as long as theoriginal. As you saw last month, removing the cancerous part always uncovers moreareas that need proper treatment. There's hidden rust, dirt, debris, andold undercoating that needs attended to. You do not want these things tocontaminate all your hard work and cause the body to reject your newpanel. Take the time and spend the effort to treat these areas, and youshould never have to be concerned about a relapse again. Prepping the new Year One... Prepping the new Year One panel starts with cutting off the top portionat the body line, and then removing the lips at either end, the doorjambedge, and the edge around the taillight opening. This way, as much aspossible of the factory look is preserved. No two cars were assembled exactly the same. In fact, the same car isnot the same from one side to the other. Everything wasn't intended tobe perfect, it just had to be within an acceptable tolerance. Now if youadd thirty or so years of usage and maybe even a bump or two, you cansee why no car is going to be perfectly "square." The reason we are reminding you of these things is that even when usingquality reproduction panels, each panel must be custom-fitted to eachcar. Prep work is never fun or glamorous, and it sometimes doesn't looklike you are really accomplishing anything. It can be dirty, dusty,tedious, and time consuming, but if you don't get this part right, thosethings that you are covering up will begin to grow again, eventuallycausing future problems by reinfecting the new parts you've labored sohard to replace. So, don't be in a hurry to slap that new panel on.Invest the effort now, and you'll be rewarded for many years to come.  The wheelwell lip on these...  The wheelwell lip on these panels tends to be a little wide, so Johnadvises using some 3/4-inch masking tape along the outside edge of thelip as a guide for the Whitney/Roper punch. This ensures the 3/8-inchholes that you punch will line up properly with the inner wheelwell lip.Once the two lips are plug-welded together, the excess lip will beremoved with a grinding disc.  The e-coating must be removed...  The e-coating must be removed from all areas that will be welded toprevent the e-coat from contaminating the welds, which could causeporosity problems. Use a 3M bristle brush for the flat butt weld areasto avoid heat warping. A Clean and Strip Disc is fine for theplug-welded seams.  Don't forget to clean a generous...  Don't forget to clean a generous area around the marker-light opening inthe new quarter-panel, as this part will be removed during theinstallation process.  The initial panel alignment...  The initial panel alignment is critical. since most of the originalfactory attachment points have been retained, you'll have a surprisingamount of leeway, and, in this case, you can focus most of yourattention on that long body line that runs the length of the panel andon the opening around the wheelwell.  Once you have your panel where...  Once you have your panel where you want it, drill a couple of 1/8-inchholes through both the new panel and the original quarter, and insert acouple of Cleco fasteners about 1/2 to 3/4 inch from the top. If youdon't have Clecos, small sheetmetal screws will work.You will also wantto clamp together the seams fore and aft of the wheel opening.  When you are satisfied the...  When you are satisfied the panel fits like you want it to, start on thetop of the panel in the middle, and begin adding additional Clecos allthe way around both ends about every 6 to 8 inches. You'll probably needto reclamp the lower seams as you go. keep checking to make sureeverything is staying lined up.  This is how far off the new...  This is how far off the new marker-light opening would have been if wewould have used the opening from the new panel. It might not look likemuch, but it would effect how well a new bumblebee stripe will fitlater.  Next, grab your West Cut 4-inch...  Next, grab your West Cut 4-inch cutoff wheel, make a slice through bothlayers of sheetmetal, peel back the two strips of the new panel, andplace a tack weld right between two of the Clecos. Now, working onalternate sides of that first weld, place additional tack welds about1-inch apart, keeping the heat to a minimum. Use a small screwdriver tomake sure that both panels are lined up perfectly. John likes the WestCut wheel because of the thin cut it makes. It leaves a gap that's justright for tack welding the two panels together.  When you get to the end of...  When you get to the end of your first slice, pull another Cleco, makeanother cut, and keep adding tack welds about one-per-inch. Once you arethis far, it's OK to keep going in the same direction. Just be sure toquench each weld to avoid heat warping. It's important to know thatthese new panels are higher carbon steel and thinner than the originalbody panel. You have to treat them as dissimilar metals. By weldingevery inch, you are using the previous weld to hold the gap from closingor spreading. You definitely don't want the weld to pull the panelstogether, as that would distort the shape of that upper body line.  It's important that the panels...  It's important that the panels are flush when you add each tack weld.You'll be grinding the welds flat later, and you'll need the panels tobe even when you do. It's amazing how sensitive your index finger can beto differences in panel height.  This is what your first round...  This is what your first round of welds should look like in terms ofspacing and size.  Use some extra caution around...  Use some extra caution around the marker light area. This is a flat areathat is more vulnerable to heat warping. Also, don't cut all the wayaround the marker light at the same time. Cut one side, then tack it inplace before you move on to the next side. It's not all that difficultto bend this marker light "ear" out of shape. But once you've got ittacked in place, you can see how the original marker light is now partof the new panel.  The doorjamb can be another...  The doorjamb can be another sensitive area. Work with the door closedand watch that you don't distort the gap as you tack weld down the jamb.If you do run into trouble, simply recut the gap and start over. Onceyou have tack welded all the way around, go around again, placinganother spot weld in between each of your previous welds.  For round three, do it again....  For round three, do it again. Put another tack in between each oneyou've already done. At this point, your tacks should be about a quarterof an inch apart. Don't get lazy here, and neglect to quench each weldas you go. True, it's less sensitive to heat warping now, but you don'twant any warping.  At any point now, feel free...  At any point now, feel free to plug-weld the wheelwell opening and thelower lips under the car.  Before you finish closing...  Before you finish closing the gaps, use a 24-grit disc to take the topsoff the welds you've done so far. You're not trying to grind them flush;you just want to make it easier to see what you are going to do next.  At this point, your gaps should...  At this point, your gaps should be about a quarter of an inch apart.This next part involves closing each gap with three tack welds in quicksuccession. IMPORTANT: This is not stitch welding. Do not ever run evena bead. Think of it as tack welding the tack welds together, instead oftack welding the panels together. The welds simply flow out and grab thepanels in the process. Do every other gap first, and then come backaround again to finish your seam.  This is what your finished...  This is what your finished seam should look like.  Next, John likes to use a...  Next, John likes to use a 3M reinforced weld-grinding wheel to grind theweld down almost flush with the panels, leaving only a very slightcrown. It's important not to touch the panels with the grinder, as theycan get too thin real quick. By leaving a slight crown, you are erringon the safe side.  Here's your finished seam....  Here's your finished seam. Run a wire wheel around the seam to make surethat any pits that remain are completely clean so the lead work thatfollows will bond securely to the entire seam.  The next-to-last step in this...  The next-to-last step in this process is applying a coat of lead (bodysolder) to the entire welded seam. John emphasizes that this is not areplacement for body filler. It is to ensure that any pinholes areplugged to protect from any moisture getting to the backside of the bodyfiller. Just apply a minimum amount of lead per Eastwood's instructions.  You're almost there. Smooth...  You're almost there. Smooth out and feather the lead with a new 8-inch24-grit disc. Run the disc fairly slow and leave the coarse grit marksit produces; they provide a great bond for the body filler. Here's whatyour finished seam should look like. All that remains is to apply a thinskim coat of body filler using standard techniques, and you're ready forprimer and paint.  These are the grinding/cutting...  These are the grinding/cutting tools that John prefers. From the lowerleft hand corner: 3M Clean and Strip Disc, West Cut 4-inch cutoff wheel,3M Bristle Disc, 3M 3-inch. 36-grit grinding disc, 3M reinforcedgrinding wheel, 3M 8-inch, 24-grit grinding disc, and a 3M dust mask.
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