Welding to thinner sheetmetal question-

[Clint]

The stuff we used came in a tube and was applied like caulk you would use on tile. The panel we "glued" on was the side of a truck bed, so it was fairly large, but only needed clamped along the top bed rail and a few places where it met along the bottom.

 

[MJ_Chubs]

3M, Lord, and Loctite would be good places to start. I used a combination of Loctite structural adhesive, self-drilling screws and structural rivets to patch the floorpan in my MJ.

Went from this:

To this:

 

[old_man]

The stuff comes with a nozzle that is about 6 inches long. The adhesive mixes in the nozzle.

 

[roscoecoltraine]

i hear that you can drill holes into the thinner sheetmetal and then take the reinforcement plate, put it behind the thin sheetmetal so you can see it through the holes and tack it at the holes. From what I understand, that is how they weld the unibody. Just a though. Im not sure if thats what your looking for though.

 

[GSequoia]

Hey Ron. If we can't afford a Pulse MIG can we just get a buddy to flip the switch REALLY fast on and off?

 

[Israel]

Hey Ron. If we can't afford a Pulse MIG can we just get a buddy to flip the switch REALLY fast on and off?

You can't flip a switch fast enough. You'd need to buy a push button start and tap that thing like you were back in your video game days.

 

[JohnR]

I work a little with sheet metal, but the only pic I have on-hand is of 18gauge sheet metal L joint. .023 wire, straight co2.

Best way to NOT warp the panel is to do overlapping spotwelds in small sections, but a simple tack isn't enough. You have to run it hot (seems counterproductive, but a short and hot spotweld has less heat to surrounding metals than a long and cool tack). Basically turn the wirespeed down, voltage up, and hold it long enough that the toes wet really well, then move foward to the leading edge of the previous spotweld, and hit it again. So in the width of a single spotweld let's say, 3/16" diameter (yes I realize the toes and the root should be equal, however the only downside is slower desposition rates and wasted wire), there would be 4 or 5 overlapping tacks by that time. Do an inch or two at a time, and let it cool NATURALLY. Flopping a wet rag over the hot metal is the SUREST way to cause warping as well as some funky internal stresses that cannot be released except by annealing and peening. Not really neccessary for sheet metal, though

 

[Rust Heap]

We use a lot of 3M products at work and they perform very well.

3M #5036 for steel
3M #5047 for aluminum

http://solutions.3m.com/wps/portal/3M/en_US/Automotive/OEM/Solutions/Exterior/Structural_Adhesive/

 

[BIGMO32]

if your set on welding it you should use a tig, otherwise id look into going the adhesive route. there are ways to mig the sheetmetal without getting heat distortion but its alot easier to just tig weld it.