O/A welding inside a vehicle

[Nikkormat]

As I sit here 1000 miles from my project I've been thinking about what all I need to get done on it next summer.

The biggest issue as I see it is the rust. The passenger side rear floor needs to be repaired, and there is some quarter panel rust to deal with.

The welding process I'm best at by a long shot is oxy acetylene. It's slow, it's easy to control, and I had a great teacher. I've also got torches and tanks I can borrow for really cheap. Just a refill. But I've never welded on anything but dumb little projects in the weld school. Let alone inside a vehicle.

I'd be taking the whole interior out except the dash which would get covered in a fire blanket. So no problem there as far as I'm concerned. The gas tank has to come out anyway so that will be out of the equation. But how do you address the paint, grease, and other crap all over the panels? People already light there cars on fire with a mig. I can imagine a torch would be even more prone to doing that.

Is it even a concern? Do I just need to keep an extinguisher around? Is O/A welding inside the vehicle just a bad idea?

[SJTD]

You should be cleaning the area anyway, right? Just need to clean a lot farther away from the joint for gas.

Problem with gas is it's slow and you'll get more warping since you'll be putting more heat into the metal.

[Tatsadasayago]

I learned to keep a putty knife scraper on hand to remove any flammables near the weld area. A brief heat-up and even the factory caulking comes loose quite easily. The same goes for undercoating if present.
A large spray bottle full of water makes quick work of any paint/grease fires as well as several shop rags soaking in a 2 gallon pail should things get 'Interesting'. The last time I replaced floor steel I used flux covered brazing rod with great results as the required heat isn't as high. Very little warpage and that was my fault for being a terrible welder.

[Nikkormat]

Brazing, man that's a dirty word some places. I've never done it but I watched a guy braze my dipstick tube back together and it's still holding strong...

I've heard it's bad news because you can't get the flux out of the joint, and they say that will inevitably cause more headaches than it's worth.

Is that a valid concern? Would you use it for body work?

[az chip]

I have been watching videos on youtube on floor pan welding. That guy keeps a air nozzle on his air hose. Tacks a spot then cools it with air. Seems to work.

[Tatsadasayago]

Brazing, man that's a dirty word some places. I've never done it but I watched a guy braze my dipstick tube back together and it's still holding strong...

I've heard it's bad news because you can't get the flux out of the joint, and they say that will inevitably cause more headaches than it's worth.

Is that a valid concern? Would you use it for body work?

I do quite a bit of silver solder brazing with a tub of flux on firearms etc. The same principles apply, wed then brush quickly. I'm not entirely convinced that flux left in the weld is a bad thing, but I'm no pro. I had a 69 Cherger I swapped in new trunk and quarter panels on with brazing rod back in the early 90s that is not showing any signs of bubbling etc.

[Tanker]

Brazing would be fine on the did that in a MG. Its like solder but better. If you need to practice take old park plugs and coat hangers an make horses out of them. Keep water and fire extinguisher handy plus soaking wet rags.

[candymancan]

Keep a bottle of water near by or something to pat the fire out.. I had water and my little extinguisher.

I've set that little carpet on the bump by the bench seat on fire once when i welding the corners that rotted near the bump on both sides lol.. Good smack knocked it out. I couldnt remove the carpet due the screws being BEEPED up so i had to weld around it. Also set on fire some of the body sealer from factory. It isnt a big deal. Its not like itll spread like gasoline

And for welding on the drivers side, which was coated in oil on the bottom. I just went slow.. Like a 1 inch line and stopped and checked under neeth in case the oil caught on fire. Which it did once but soon fizzled out a second later. I guess it sounds dangerous maybe, but there is no way to clean that floor down there with the frame, and body mount/ tranny and all that stuff in the way

[Tanker]

Also have a person watching for fires if you can. Try not to set your self on fire either. Did Halftrac floor on her J 10 cheap bathmats an roofing cement layerd about 4 layers thick. Was using mig an set myself on fire several times as well as the truck. Wife caught it in time.