10/19/2005: Metalwork 8: Now It’s Serious.
Sorry for the delay in posting this update.. I’ve actually been doing quite a bit on the car lately, but haven’t gotten around to writing about it. Also, my camera has been acting up, and finally died, so for the moment I’m relying upon my camera phone, so the quality is not so hot. I’ll get a new camera soon, if I can’t coax my old one into working again.
The rear panel of my car had several large dents, but since there’s no way to get to the back of this panel, i couldn’t really fix them very easily. A few months ago, I was able to get the back foot or so cut off of a rusted out parts car, and it included a “decent” version of this panel. I decided to cut the panel off my car and replace it with the other.When the car was built, the rear panel actually extended forward around the trunklid, all one piece.
It’s not practical to remove this in one piece, just to repair a dent in one section of it. Therefore I decided to cut vertically about an inch in from the tail light on each side, then diagonally into the seam.
First, I welded a piece of angle iron across the opening, just to keep things lined up in case it got floppy once the rear panel was removed. Then I drilled out all the spot welds along the bottom of the panel carefully, then sliced up the sides and across the top. After that was done, I ground away the remaining top section of the panel, leaving the inner reinforcement intact.
I was happy to find that there’s almost no rust on the inner reinforcement panel. Before I put things back together, i’ll just hit it with a coat of POR-15 to keep it that way.
This panel was originally quite dented. I removed these dents some time ago, but the bottom few inches of the panel were also rather rusty. My original plan was to fabricate a patch panel, and in fact I did make one (You can see it laying across the back of the car in the pictures above, in fact).
However, once I removed the original rear panel from my car, it came off so intact that I decided to use the bottom few inches of it instead of my patch. So I measured carefully and cut both panels, then tacked them together:
This was done very slowly, working from the center out. I used 4 or 5 clamps and made sure the alignment was perfect after each tack before continuing.
Then I went back across and connected the dots, using either continuous stitches or a series of tacks to fill the gaps. (I was having some trouble with burn-through, so I switched to the tacks part way through the job. They’re a lot easier and less likely to burn through).
I still need to adjust the panel a little bit (hammer and dolly, shrinking disc) to deal with some distortion that was introduced by the welding. I may also go back and fix a few areas where the weld didn’t penetrate as well as I’d like.
Then I can finish trimming it to fit the opening and weld it back into place. Before I do this though, I want to re-fit the trunk lid, so make sure that the gaps are even.
I’m quite happy with how this repair is turning out. It will certainly require some filler to hide this weld, but not much, and I think the final result will be very seamless from both the inside and outside of the car.
This whole process is not a quick one. I’ve been putting in a few hours each night for the last 4 or 5 days, and there’s still more work to do. I certainly could have just slapped filler on the old panel, or flanged it and lap welded the repair section, but for this repair I really wanted to try the butt weld technique some more. It’s hard work, but good practice. I’m definitely learning more each time I do this stuff.