One of the most common areas for rust for any car from the muscle car era is the rear quarter-panel. The front fenders and framerails suffer quite a bit as well, but the rear quarters have a habit of harboring and fostering the proliferation of rust, especially for vehicles driven in the snow belt. Combine that with poor metal plating and minimal rust prevention methods and you have a recipe for car cancer. The eventual replacement of the quarter-panels is not a process that should be taken lightly, and if full quarter-panel replacement is in the cards, then you really want a professional handling the installation.
If you've been following our Colt of Personality '66 fastback project, you may recall that we took the Pony up to Graverobbers Sheetmetal in Cumming, Georgia, for its mini-tub conversion on the rear wheel wells. We learned a lot by hanging out with the staff and watching them work the metal on the car. They also like to educate their customers as to what to look for when it comes to buying a car in need of restoration. We ended up having Graverobbers replace a number of panels on the car, including both rear quarters. Here's how they did it.
1 Knowing what to look for...
1 Knowing what to look for comes from experience, and the staff at Graverobbers has plenty. Owner Jeff Kipfmueller was the one that pointed out that the pitch at the top of the quarter-panels was off, as shown here. It would later appear to us that two different individuals took turns at replacing the quarters previously, and both managed to do a bad job.
2 Graverobbers constructed...
2 Graverobbers constructed its own vehicle-specific jigs on which project cars are mounted. The jig supports the chassis at the original production line points, and this allows the staff to retain all of the critical OEM dimensions as the sheetmetal is replaced. Having been at a number of restoration shops where cars have been taken down to their bare skeletons (yes, there actually is one), you'll understand why supporting the car properly is important. It's also important to note that when welding on the new panels, you can easily warp the panel itself and tweak the chassis from the heating and cooling of the metal, and using a jig can help prevent this.
3 There are often different...
3 There are often different kinds of quarter-panel replacements, such as partial, half, and full pieces. The extent of damage to your present panels will often dictate which of these to use, and what tools you will need to remove them. Here, Kipfmueller uses a metal shear to remove the majority of our quarter-panel.
4 The inner and outer wheelhouses...
4 The inner and outer wheelhouses had already been removed on this side prior to the quarter-panel coming off. You can see that the quarter attaches to a number of other components on the car. While this helps add support to the rest of the chassis, it also intensifies the need to make sure they are installed on the car properly so as not to move anything else out of alignment.
5 If you look closely, you...
5 If you look closely, you can see the popcorn-like welding that was attempting to hold the present quarter-panels on to the car. The "surgeon" also left part of the original panel in place, making for both a sloppy and weak installation.
6 The new Goodmark sheetmetal...
6 The new Goodmark sheetmetal comes with an E-coat on it, but you'll still need to punch the factory spot weld holes for installation.
7 Whether you are installing...
7 Whether you are installing new wheelhouses, or using the factory pieces, you'll need to test fit and trim the quarter-panels as needed, since production variances both in the original and the aftermarket sheetmetal can be significant enough for things to not line up exactly. Be sure to measure twice and cut once for exact fitment before welding.
8 Here, Graverobbers fabricator/installer...
8 Here, Graverobbers fabricator/installer Berlin Lopez test fits the new quarter-panel. Take your time here, as the quarter-panel sets the alignment for the tail panel, decklid, doors, rockers, and roof.
9 As you test for the panel,...
9 As you test for the panel, make sure you compare the fender angle and that it is consistent from side to side. Given the production variances from the factory, it can be difficult to pin down an exact angle. If you have access to an untouched, original specimen, base your measurement off of that. Just be sure the specimen is level before measuring.
10 Self-tapping screws or...
10 Self-tapping screws or Cleco-style sheetmetal holding pins can be used for initial quarter-panel fitment. This will allow you to work the panel and fit it to each of the other components it is fastened to.
11 As Lopez is shaping up...
11 As Lopez is shaping up the final fitment of the panel in this photo, it really illustrates how the quarter-panel is really one of the key main structures of the car, and how it carefully ties the back of the chassis together.
12 Once you're happy with...
12 Once you're happy with the overall fitment of the panel, you can begin stitch-welding it to the car. Small tacks around the perimeter are followed by longer beads. It's important to keep moving around so you don't warp the panel from the heat of the welder.
13 The front seam at the...
13 The front seam at the door is welded together with a MIG welder. This is stronger than the factory setup.
14 Where there would normally...
14Where there would normally be just a couple of spot welds attaching the wheelhouse to the rocker, Graverobbers welds a complete bead in here, as well as in many other places on the chassis. With today's modern powerplants and increased power levels, Graverobbers feels that adding strength to the chassis is essential to the longevity of the chassis, and subsequently, the paintwork. While we happened to be installing new mini-tub wheelhouses at the time, quarter-panel installation is also a good time to take advantage of the interior access you normally wouldn't have to accomplish such measures.
15 Welding on the quarter-panel...
15 Welding on the quarter-panel is nearly complete. The wheelhouses and bottom section where it meets the trunk drop off will be welded next.
16 Having a skilled metal...
16 Having a skilled metal worker on hand can make it easier to pick out any imperfections in the panels and have them easily repaired. Lopez caught a small ding in our new panel and used a hammer and dolly to straighten it out.
17 The final welding touches...
17 The final welding touches on the quarter come from the spot welder, just like from the factory.
18 With our new quarter-panels...
18 With our new quarter-panels and taillight panel installed, we can now move to the bodywork and paint. The Graverobbers/Goodmark mini-tubs add a custom touch, as does the now much wider rear rubber!