Adhering sheet metal without Welding?

[A930Rocket]

I was working on my 330 track car today and I wanted to roll the rear fenders for wider tires. The fender roller didn’t work, due to the two layers of sheet metal, so then I moved to the BFH.

The hammer worked to an extent, but I could not get it as flat as I wanted. So, I came up with the great idea to use my cut off wheel to cut back the inner wheel lip and flatten it with the hammer, then weld it.

It worked good until the welding part. I totally botched it up, burned some holes in the inner fender and could not get the two pieces to weld. My Mig welding skills obviously suck.

Being a track car, looks don’t matter to a degree. Is there some kind of automotive adhesive that I can squirt in between the two pieces of metal to adhere them and fill in any holes?

Once I am finished, I will use seam sealer or under coating to cover everything.

Right now, JB Weld is high on my list.😂

Edit: with hindsight 2020, the other side worked like a champ, because I left a little more metal to work with. I was able to fold it over the inner fender.

[Shaun @ Tru6]

3M Panel Bonding Adhesive, 08115, OEM Recommended, Two-Part Epoxy, 200 ml/6.75 fl oz Cartridge

[Ayles]

What about epoxy with some sort of filler so it doesnt run out the cracks? Something like west systems?

[Tishabet]

Originally Posted by Shaun @ Tru6

3M Panel Bonding Adhesive, 08115, OEM Recommended, Two-Part Epoxy, 200 ml/6.75 fl oz Cartridge

This exactly, the special mixing gun will set you back but this stuff is the real deal. I know people who have affixed entire body panels with this stuff when restoring cars instead of using the factory approach of spot welding, result was excellent.

[Zeke]

I'd keep welding using the 'stich' method. I have, and many other people have welded up a 3/8ths" hole with MIG.

[A930Rocket]

Originally Posted by Shaun @ Tru6

3M Panel Bonding Adhesive, 08115, OEM Recommended, Two-Part Epoxy, 200 ml/6.75 fl oz Cartridge

I saw that earlier tonight. I’ve got a run some errands tomorrow , so I’m gonna go by a body/paint shop and see if they have some.

Originally Posted by Zeke

I'd keep welding using the 'stich' method. I have, and many other people have welded up a 3/8ths" hole with MIG.

I did try to stitch weld. I don’t think my skills or mig welder are up to the task. It’s only 110V, so that might be some of the problem.

[zakthor]

Originally Posted by Zeke

I'd keep welding using the 'stich' method. I have, and many other people have welded up a 3/8ths" hole with MIG.

Right. I'm terrible welder and what you have doesn't look so difficult. Get some thin sheet and play with butt welding it until you get the feel. I sure wouldn't try a chemical fix now that I have a mig.

Just a little mig zap and wait for it to cool so you can touch it with your hand. Repeat. Then maybe grind flat and hose it down with metal primer.

https://youtu.be/U9iki7bQblc

Or find someone who can weld to do it for you.

Edit: 110v is no problem there's no issue with power when you're welding thin sheet. Issue is too much heat. Bigger problem is old rusty welding wire or a stuck wire feed. New modern mig wire is amazing.

[A930Rocket]

^^^^^ I might as well give it another try tomorrow, and see what happens. What I don’t want to do is somehow burn the outside edge or exterior paint.

[otto_kretschmer]

if you're blowing holes in the steel sheet, you are using too much current

I would keep trying with the welder until you figure it out, its a skill worth having

I welded the fenders back on my 76 after I abandoned my wide fender project.

If you're using flux core, it will be more challenging but still can be done. A shield gas kit makes it easier.





https://forums.pelicanparts.com/porsche-911-technical-forum/816906-skinny-fat-skinny.html


a non-pro tip: when welding my fenders back on I went to home despot and bought a short length of copper tubing, maybe 1" dia. One end I took a hammer to and smashed flat about an inch. I used the copper to place behind the gap I was trying to fill. The filler wire will not fuse with the copper and the copper acted as a back stop. This made filling the gap much easier.

[Heel n Toe]

Urethane Construction Adhesive - accept no substitutes

[Tishabet]

Originally Posted by A930Rocket

I saw that earlier tonight. I’ve got a run some errands tomorrow , so I’m gonna go by a body/paint shop and see if they have some.

You also need to proprietary caulking gun thing and the mixer tips:
https://www.amazon.com/dp/B002QWYG1O
https://www.amazon.com/dp/B0015PI2UY

So about $130 all in

[zakthor]

Originally Posted by A930Rocket

^^^^^ I might as well give it another try tomorrow, and see what happens. What I don’t want to do is somehow burn the outside edge or exterior paint.

You want to preserve paint? Uh.. my trick is my mig gun can flow gas without arc or wire, I use it to keep paint/calk/dynamat from igniting until it can cool. Maybe a block of copper on the other side to absorb the energy? But I think you can’t weld if you actually want to save the paint.

[A930Rocket]

I have a copper spatula for welding, but the backside is not accessible. Also, my tank of argon ran dry, so that was probably another factor that didn’t help. I’ll pick another one up today.

Question: what size wire would be best? I believe I have a .30 wire in the machine now.

[Bob Kontak]

I have to think 0.023" would be better for a non pro welder.

Gas is important.

If you get the panel adhesive get the gun as mentioned. It works well.

[A930Rocket]

Thanks, guys.

I’ll let you know how it works out over the weekend.

[Shaun @ Tru6]

Originally Posted by A930Rocket

I have a copper spatula for welding, but the backside is not accessible. Also, my tank of argon ran dry, so that was probably another factor that didn’t help. I’ll pick another one up today.

Question: what size wire would be best? I believe I have a .30 wire in the machine now.

That's a lot of wire for what you are trying to do. I use .024 for all sheet metal work.

Also the whole area needs to be a lot cleaner if you are welding.

And I don't see how you can get a good weld AND NOT burn exterior paint.

Being a track car, construction adhesive may be the way to go. $10 and 5 minute job and you are done.

[A930Rocket]

Shaun, you might be right. That picture is from the left side, which came out a lot better, with cutting and folding. No welding. I was too embarrassed to show a picture of the right side, which was prepped much better for welding

With the outside metal folded over on the inner fender, I didn’t know if the heat will transfer to the paint. My thought was to keep the stitches very small and hope for the best. Most likely, I’m going toend up painting about an inch of outside fender lip.

[T77911S]

the guy I bought mine from was telling me about some rear flares for the rear.
and then said use M3 fronts.

I can get 265's on mine. 8.5 rim with a 50 offset.

[A930Rocket]

Originally Posted by T77911S

the guy I bought mine from was telling me about some rear flares for the rear.
and then said use M3 fronts.

I can get 265's on mine. 8.5 rim with a 50 offset.

I’m going to use the wheels I bought for the M3 on my 330, so there’s some work to be done. They are 265/35/18 on 18 x 19.5 with a 35 ET. A deeper ET would definitely help.

I’m not sure if the M3 front fenders will fit the facelift E46. Maybe the headlights would have to be changed out? The front bumper would need to be stretched or replaced with an M3 style.

[Bill Douglas]

Got to have gas, be it argon or co2, or a mix. And as mentioned do lots of practice on thin metal and look at lots of youtubes on the subject. And once the machine is setup right you'll be fine