Anyone ever tried TIG repair to fix rusted out auto sheet metal?

[Willie B]

Most of a lifetime ago I was building a house. Mortgage money was non existent. Prime rate was 21%, Federal Government put a cap on mortgage money at 15-1/2%.
To say the least, money was tight!

Mrs. B wasn't yet Mrs. B, she was in college 120 miles away. I bought her a car I could afford. An Audi 100LS. I describe her as an automotive hypochondriac. Always a "funny noise" or some other non existent problem. She'd come home for a weekend, I'd spend much of the weekend working on her clunker car.

One weekend she came up with a good one; "The seat sits funny."
"Oh Nancy, you're killing me!"

Saturday morning I had her drive me to the lumber yard. I used their truck to haul home my purchases. The owner, being a good guy hopped in the driver's seat tp follow me here & help unload. He got out of the car and said; "The seat sits funny!" Word for word, exact quote from what Nancy had said.

"Oh Elbert, Give me a break."

Sunday at 6:00 PM she swung herself into the car. When she adjusted the seat, it dropped through the floor. She was sitting on the driveway!

11 hours later, I had replaced the floor & she was able to go to school.

[RoatanBill]

When she adjusted the seat, it dropped through the floor. She was sitting on the driveway!

She was lucky it didn't decide to fall through when the car was moving.

[smithdoor]

I have seen in the past using brassing then bondo.
https://www.3m.com/3M/en_US/bondo-us/

Dave

I've watched several videos of people supposedly in the know about how to fix a rust spot on a car panel. They all MIG spots all over the edge of the patch until the entire perimeter is a pile of tacks. Then they sand off the excess and it looks pretty good. The underside looks like Fido's butt but the top surface is fine.

I was wondering if anyone has used TIG to do such a repair job. It would appear to me that a TIG repair would have better patch to panel fusion and much less grinding afterwards. I also suspect much better control for blending in short stitch welds to avoid a buildup of heat in any area.

A concern is the back side of the panel and what primer, paint or other junk it might contain that could screw up a TIG weld. MIG is less picky about such things.

[Mike_L]

I've been thinking of epoxy also. If I enlarge the hole to a rectangle 1"x2", then I can insert a piece of sheet metal 1-7/8"X 3" and rotate it 90 degrees to cover the hole from the inside. Once that's set up, I can then epoxy in another patch to cover to hole from the top.

At least I won't burn the vehicle down.

If you don’t want to remove the interior parts and headliner that may be your beat bet. 3M makes some panel bonding adhesive that, once it sets up, isn’t going anywhere. Some quarter panels on newer cars are attached this way. You could even put body filler over the top, finish sand and repaint. It’s not an approved method, but for a temporary patch on something that’s not a new vehicle I think it would be ok.

Only issue I can see is that the panel bonding adhesive needs bare metal, wouldn’t be a problem on the patch piece but I’m not sure how you would sand down the coatings on the roof panel. A Dremel with a small disc might allow you to reach through the hole and sand the underside of the roof panel.

Here’s the adhesive I’m talking about, I chose Amazon as I figured they might be the easiest supplier that would ship to you.

3M Panel Bonding Adhesive, 08115, 200 mL Cartridge https://www.amazon.com/dp/B000PEW4MI/ref=cm_sw_r_cp_api_glc_i_fIr6Fb1TX8VMP

[RoatanBill]

Thanks for the URL.

I figured if I wind some sandpaper around my finger, I can scrub the underside and inspect it with a dentists mirror to make sure it's clean. I can hold the patch in place with a magnet till it sets up. I've got some 1"x2"x1/4" N50 magnets I use for welding work that would be ideal for that task.