Trunk Patchwork

Current Trunk-Lid with Rust Damage

The trunk-lid looks good except for one small section on the driver's side where it was rusted through. When I first bought the car I figured that I would simply buy a new trunk, but after realizing that I had sheet metal to replace the cancerous section, I went down that path. My first Mustang's trunk had been hit on the passenger's side prior to me first buying it and it had a log of Bondo so using it on my current Mustang was out of the question. Since the driver's side was in great shape, I decided to do some patchwork

Current Trunk-Lid after Rusted Section was Cut Off

I had to be careful when cutting out the cancerous section as to not cut into the existing trunk below. The sheet metal laid over the frame and wrapped around underneath and was held on by one spot-weld.

Trunk-Lid from my First Mustang

After stripping off the layers of paint on my first Mustang's trunk-lid, I marked a section slightly larger than the one I cut off of my current Mustang; better to have to cut more later than to have cut too much up front.

First Mustang's Trunk-Lid with Donor Section Cut Off

As you can see above, there was some surface rust inside my first Mustang's trunk as well, but it hadn't rusted through to the lid.

Current Trunk-Lid with Donor Section Welded in

Once I had the donor piece in hand, it took about another hour of careful grinding using a hand air-grinder  to custom fit it. Once I had it perfect, I beveled each side that met to form two 45 degree angles to create a valley in which I could fill with a weld. I tested the heat and speed of the line on my original mustang trunk lid and we had to turn down the heat to the lowest setting (A) and the speed to slightly under 4/10. When I was done welding, the bead of weld sat above the flat surface of the trunk lid so using the air-grinder I made it as flush as possible.

Welder Settings

The final step will be to use a skim coat of Bondo to ensure an even and smooth surface. This will happen over the next few months when I begin to piece the car back together and begin to do bodywork in preparation for paint this summer.