The 1983 sub-frame has long tabs welded on each leg that help hold the side covers on. But, on one leg, both the top and bottom tabs are broken off. Before I have the sub-frame powder coated I repair these.
The profile of the tab has two curved sections that join to a straight section in the middle and I want to duplicate that profile.
The original steel tab is 1 mm thick (about 20 gauge) and 10 mm wide (about 3/8 inches).
I use some scrap steel grass edging i have laying around. It’s 1 mm thick and made from mild steel. I cut a 10 mm wide strip about 6 inches long using my Dremel with a cut-off wheel. Six inches is long enough to make two tabs.
Forming A Tab
I shape the strip to match the profile of the existing tabs. I can bend it by hand around the existing tab where it is welded to the sub-frame tube to start forming the larger curve that is welded to the tube.
To finish that curve, I use a 12 mm socket and continue to bend the strip using my fingers until it gets too hard to bend. I finish up using a hammer to complete the curve pounding the strip around the socket while resting it on the flat anvil surface of my bench vice.
Next, I mark the start of the straight section using the original tab as a template and bend the strip to the same angle starting with my vice and finishing with my fingers. I use a large diameter drift and a hammer to flatten out the straight section on the flat of my bench vise.
I mark the other end of the straight just before the beginning of the flare with the slight curve in it. I bend this section using a drift and my vice to get the curve in the end of the strip.
When I get the curve to match the original, I cut off the excess metal on the end of the strip with the Dremel cutoff wheel. I use a Dremel grinding stone (you could you use a flat file) to round of the end of the tab.
I use my flat file to dress the strip and remove the sharp edges so it won’t cut me.
The profile for the bottom tab seems a bit different than for the top, so I used the bottom tab as a template for the bottom strip. When I finished, I marked them “T” and “B” so they will be welded in the proper location.
I suspect the tabs were originally identical and they have been bent a bit with use over the years. But, to avoid a surprise should they have been different, I made each replacement based on the profile of the top and bottom original tabs as it’s not any more work and removes a possibility for error.
Welding Tabs To The Sub-frame
My son, Branden, is a pipe fitter. I took the sub-frame and tabs to him to weld. We started by marking the location of the original tabs and then ground them off.
We aligned the tabs with the marks and clamped them to the sub-frame.
Branden spot welded them using a MIG welder, but a TIG welder would have been the better choice. Unfortunately the TIG welder was not working. Here is the final result.
All set to take this for powder coating.