M. Quarter Panel Removal
Post date: Aug 23, 2015 1:7:47 PM
There was an obvious repair made at some point to the passenger side quarter panel and there was a good bit of rust present behind the rear wheel. While the drivers side quarter looked OK it was decided to replace it at the same time. Both sides will be using NOS GM quarters that were acquired for this job. Before the bed panels can be welded back in the quarters must be removed as they have a flange that is sandwiched between the bed back panel and roof structure.
The process begins by removing the majority of the quarter panel sheet metal to leave a strip of metal around the perimeter where it was spot welded to the mating panels. Once this is done, then the spot welds can be drilled or ground and the remaining ribbon can be removed. Using a cut off wheel as well as an electric metal shear the panels are removed.
While it looks dramatic, the real work is ahead because removing the spot welds is a time-consuming process. We choose to drill each weld or use a grinder to thin the weld and then use a body knife to separate the panels. Others just use a pneumatic chisel and while this is effective, it runs the risk of damaging the remaining panel if not very careful.
As noted before, there was evidence of some prior bodywork on the passenger's side quarter panel and now we can see just how much - this seems consistent with the body work done on this car in other spots. I suppose the one doing this gets an "A" for making it look passable, but this is no way to do body work. There was well over 1/4" of filler along the side of this quarter panel - miracle it hadn't cracked.
After about 2 hours the passengers side panel is nearing completion with the door jam and sail panel yet to be done. The sail panel area needs to be addressed, but that will be done once we determine where we will be welding the new quarter to the structure in that area.
In all the underlying sheet metal looks very good. Some surface rust to be removed and a few very minor patches to be welded in, but a great foundation for this repair!
So now the leaded seam between the roof and sail panel needs to be cleaned out. This joint welds the roof to the sail panel and to the remaining structure. Since the quarter panel is welded under the roof panel, we will cut off the original quarter and not disturb the roof weld. When the new quarter is put on it will be butt welded to the piece of remaining quarter which accomplishes two things - it doesn't disturb the roof and the weld will be in the "valley" of the seam which gets filled again anyway.
To remove the lead use a MAP gas torch and fold a wet towel to put on the roof above the seam just to dissipate as much heat as possible so you don't distort the roof. Heat up and area and with a wire brush clean it out. Do this in an area with good airflow and don't breathe the lead - it's not good for you!
With the lead removed from the seam (a twisted wire wheel was used to remove any remaining lead) you can easily see how the quarter gets tucked under the roof. With this done the next step is to break the spot welds that hold the sail panel to the drip rail. This is a bit tricky and requires a soft touch with a thin, small diameter grinding wheel (3") First you need to get a small (thin) wire wheel into the drip rail to clean out the paint and seam sealer to expose the spot welds. If you look close you can see that they've been marked on the outside of the rail with a yellow grease pencil. Once you have located them you want to grind the sail panel metal just enough to release the weld. You do not want to grind through the drip rail.
Once the welds are broken you can make the cut across the top of the sail panel and then break the remaining piece away. I am over-simplifying this - this is a tedious process because the sail panel is also spot welded in the window channel as well as the bed side wall. Take your time, do it in small pieces and when you are done it looks like this - a completely removed quarter panel from a 1970 El Camino - cool huh?