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1973
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Front Column Repair

The front columns, or lower a-pillars if you like, are crucial to the structural integrity of a 2002. They serve as mounts for the door hinges and tie the rocker panels to the front of the car. Initially, I looked into the replacement factory columns that BMW Mobile Tradition sells through dealers and outfits like Maxilmillian and 2002AD. Sticker shock, however, stopped me in my tracks. These pieces at $287 each were a bit spendy for me. Now to be fair, the factory columns are complete replacements for the original section, including door hinges. But my hinges were fine and there was only rust in the front part of the column. What to do? Buy the BMW MT replacement part and throw half of it away? Try to fabricate something on my own? Solving these problems are what make a restoration fun, right?.

Left Side

The front column is located behind the inner fender panel and it was necessary to remove a section of the panel in order to gain access to the column. In some cases the inner fender may be so badly rusted that the whole section has be replaced. However, in my case it was only be necessary to repair a portion. The inner fender repair will take place later in the process.

left column 02

The inner fender support with the cut lines marked.

I began by making two nice, straight cuts with a body saw. Then I cut through the weld at the rear of the inner fender support with a cut-off wheel and peeled it back.

left column 03

Doesn't the rust remind you of one of those "ink blot" psychology tests?

Next, I removed the first four inches or so of the rocker panel. First I made a vertical cut with a body saw, and then drilled out several spot welds. Most of the rocker panel spot welds are obvious, but the spot welds that join the top of the rocker to the column support can be a bit tricky. I had to pry the rocker panel up a bit to see all of the welds.

left column 04a

Three of the four spot welds holding the top of the rocker to the column support have been drilled out at this point—the fourth spot weld can be seen as a faint dimple.

I suppose that the entire rocker panel could have been removed at this point, but I elected to leave it in place to maintain the structural integrity of the body. This section of the rocker looked basically OK from the outside. As you can see however, it was in pretty bad shape on the inside—both rocker panels will eventually be replaced.

left column 04

The front couple inches of the rocker panel (where the rocker overlaps the column support) is an evil water trap. This section of rocker panel was about to rust through.

I purchased both left and right front column repair panels from Walloth & Nesch in Germany. These panels are a great alternative to factory replacement parts: they cost a great deal less than the factory panels (about $60 each in 2003 as opposed to $287), and they repair only the areas most likely to be rusted.

Before removing the old column, I had to remove the rusty fender bracket. I took careful measurements so that new one could placed in the same location.

left column 05a

Rusty fender bracket... swiss cheese anyone?

With the fender bracket out of the way I clamped the repair panel into place and marked my cut lines. The cuts were made, leaving a generous amount of extra material, with a body saw and cut-off wheel. Spot welds were drilled out with a combination of Wivco spot weld bit and 3/8-inch spot weld cutters, plus the trusty 3/8-inch drill bit. Drilling out spot welds is just about a unglamorous, and boring as old car restoration gets!

left column 05

The repair panel was clamped into place, while cut lines are marked.

left column 06

After much cutting and drilling the panel was removed. Only additional surface rust was revealed—hooray, that's one for our team!

At this point I stopped to carry out an inner rocker repair. I made a template out of thin cardboard, transferred the template to a piece of 16-gauge sheet metal, and cut it out with a body saw. Some shaping was done with a die grinder, and then the lower tabs were heated with an oxyacetylene torch and bent into shape. The rusty area was cut out and the repair was welded.

left column 08

The front corner of the inner rocker panel needed a small repair.

A moderate amount a massaging was necessary to get the new front support to fit correctly, however, it fit much better than I expected. At this point, I decided that a small heavily pitted area just above the main repair needed some attention. I fabricated a small patch out 16 gauge sheet metal, and then tack-welded it in place.

left column 09a

A small patch, just above the main repair.

Any remaining surface rust was removed, and the whole repair area got a coat of POR-15. 5/16-holes for plug welding were made using a drill press. Finally, the POR-15 was sanded back from the weld area about 1/2-inch and some weld-through primer was applied.

left column 09

With everything painted and prepped, it was time to weld!

With column welded in, the fender bracket was placed on the support according to my earlier measurements. I tack-welded it into place and held the fender on the car to make sure that everything lined up. Then, I proceeded to plug-weld the fender bracket on to the support.

With all of the other welding a grinding out of the way, it was time to repair the rusty section of inner fender panel. I decided where to make my cuts, and then made a template out of thin cardboard. The patch was cut out of 20-gauge sheet metal with a body saw, and then two pieces were welded together. After the welds were ground down, the inside of the fender panel received a coat POR-15 before being welded back on the car.

left column 10a

A template really helps eliminate the guesswork when fabricating a patch.

left column 10

The rusted metal was removed with a body saw.

left column 11

No holes, no warpage, I think I'm starting to get the hang of welding two pieces of sheet metal together.

left column 12

After final welding and grinding it turned out looking pretty good.

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Right Side

Brimming with confidence and some free time over the 2003 Christmas holiday, I knocked out the rest of the repair on the other side of the car. For some reason, there was less rust damage to contend with and the whole job only took a couple of days. From this point on, I'll dispense with the detailed description and let the pictures speak for themselves. By this time, I'm sure you get the idea.

right column 01

Heavy pitting on the column and fender bracket are evident.

right column 02

The rear section of the inner fender panel was cut with a body saw.

right column 03

The weld seam at the rear of the panel was ground down with a cut-off wheel. Then the inner fender section could be carefully bent back.

right column 04

The fender bracket was removed using a spot weld cutter.

right column 05

The front section of the rocker panel was removed using a spot weld cutter and cut-off wheel. The rocker panel hadn't rusted through quite yet, but it was only a matter of time until it did.

right column 06

The old column section was carefully cut out using a spot weld cutter, body saw, and cut-off wheel.

right column 07

Surface rust was removed with a 36-grit disc and a wire brush on a die grinder. The whole area, including the inside of the replacement panel, got a coat of POR-15. Any stray POR-15 was removed from the areas to be welded, and a coat of 3M weld-through primer was applied.

right column 08

1/4-inch holes were drilled for plug welding. Then the panel was carefully aligned and everything was welded.

right column 09

The inner fender panel was repaired. First a series of tack welds were laid down. Then the seam was stich-welded in small segments.

right column 10

The fender bracket was plug-welded, and the inner fender panel was welded into place. After plenty of careful grinding, everything cleaned up nicely.

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