Rustoration
by Steve McManus
Introduction

I got a wild hair a week ago to fix the rust on Barney, my '56 Fireflite Sportsman. The shop was empty, the weather was bad, and I didn’t have any work lined up, so I figured I’d get started. I decided to record the process for posterity and so that it might aid someone else contemplating this kind of work. I also figured that making my rustoration public might spur me on to finish the project.

I decided to break the rustoration down into sections. This, I figured, would keep me from being overwhelmed. While Barney has a solid frame, cancer had set in and it did not seem to be healing on it’s own. The rust is significant, but not beyond repair. I decided to start on the rear quarters, then the rockers, and then the front fenders. Taken one side at a time, this would give me 6 separate projects.

Rear Outer Quarter Panel

You can see (figure 1) the obvious extent of the rust in the left rear quarter panel. First thing to do is find where the rust stops and the solid metal begins.

rust1_350 (23K) Figure 1

I ground the paint off with my handy angle grinder equipped with the 3M "sandblaster" pad. Then marked off what I want to cut away. (figure 2)

rust2_350 (28K) Figure 2

I then used my air cut off tool with cut off disc to remove the offending material. Ouch! Look at the inner rear quarter panel. (figure 3)

rust3_350 (31K) Figure 3

While the inner rear was exposed, I decided to cut that out while it was easy to reach. (figure 4) Notice the interior of the body is bare steel. No wonder he rusted out! I had purchased some rear quarter patch panels from some guy in Canada. Unfortunately, they were 3 inches too short. It turns out that the rear quarters on ’56 2 doors and convertibles are 3 inches longer than the rest of the ’56 DeSoto line up. Having been looking for several years, I determined that the correct ones for Barney were made of unobtanium, so I decided to cut and paste the patch panels I had.

rust4_350 (31K) Figure 4

After carefully cutting the patch panel to fit, I spotted it in using my mig welder. (figure 5) This is a good time to be very careful. Use patience trimming the panel to leave about a 1mm gap all the way around it. When you weld it in, alignment is critical to making a bondo free patch. Tack it every inch or so. Then fill in the gaps by jumping around. Don’t weld one area all at the same time or you will warp your body panels. Go slow. I duplicated my efforts on the aft end of the rocker panel. Then using my air cut off tool, I carefully ground down the raised portions of the weld beads. I then used the angle grinder to smooth grind the welds. After that, I metal finished it with the sandblaster pad.

rust5_350 (30K) Figure 5

So that’s what it looks like after about 6 hours of work. (figure 6) A little filler on the welds and it will be ready to paint. Before I get to that though, I need to rebuild the inner rocker panel.

rust6_350 (35K) Figure 6

Rear Inner Quarter Panel

After completing the welding on the outer rear quarter panels, I started rebuilding the inner rear quarter panels. (figure 7) The first step was to cut away all the rotted metal. Then I cleaned the surfaces with angle grinder and cup brush.

innerqtr1_350 (25K) Figure 7

I then measured the approximate size of the patch needed to replace the rust. I cut out a blank from 20 ga sheet metal and placed it in the quarter panel and marked it off with a sharpie. I then trimmed the patch for fit. (figure 8) I wanted it to be a bit larger so I could lap weld it over the remaining original metal.

innerqtr2_350 (17K) Figure 8

After much fiddling and test fitting, I finally got it cut to the correct size. Note the tabs cut along the lower edge. (figure 9) These will bend to mate with the bottom edge of the outer quarter panel. These will also serve as the weld surface for attaching the bottom of the quarter panels together.

innerqtr3_350 (35K) Figure 9

I put the bumper end back in place to make sure I had the correct contour on the quarter panel before tack welding it into place. (figure 10) Once it is welded in place, you are stuck with the contour you have. I never knew how rigid the quarter panels could be with solid metal on both sides.

innerqtr4_350 (22K) Figure 10

With everything lined up the way I wanted it, I welded everything in place. (figure 11) I also made a new bracket for the "mud flaps" and welded them to the new inner quarter panel.

innerqtr5_350 (26K) Figure 11

While cutting away the inner rear quarter panels, it became obvious that the bottom lip of the remaining original metal was deteriorated beyond salvage on both sides. As you may recall, the patch panels were 3 plus inches too short, so there is a 3 and a half inch vertical strip of original quarter panel in the middle of each side. (figure 12) So a bit more cutting and welding was needed before finishing the panels.

qtrpanellip_350 (28K) Figure 12

With all the welding done, I used my handy air cut off tool to carefully knock the high spots off of the welds. The abrasive disc only removes the material you aim it at. It doesn’t generate near as much heat as using a grinder so it doesn’t distort the panel like a grinder can. A quick scuffing of the entire surface with the grinder followed. After making sure the welds were at surface level or slightly below, it was time to fill along the welds. I considered using lead, but after talking to some knowledgeable folks, I decided to use an all metal filler. This is much easier to handle, is waterproof, bonds the panels together and sands nicely. Bondo was not a choice because it lets moisture through so it should never be used to cover a body seam. The brand names Metal to Metal and All Metal are recommended and cost about $20 a quart. Fill, block sand and repeat as necessary to achieve the desired smooth ripple free surface. (figure 13)

ltrrqtrdone_350 (21K) Figure 13