go ahead and laugh, but....

[Gentleman Jimmy]

I can weld up the holes, or I can get patch panel. Not well schooled on rust repair never tackled what little we see here.

If it were me, I would get a patch panel and or make one. You will be burning through and just making bigger holes with rust/pitting like that.

 

[ktmoutfront]

Eating up rusty metal with a MIG gun is what will happen. If you have to get it done now, put a thick piece of copper behind it as you weld. But who has thick copper laying around?

 

[Wes Harden]

I actually have a copper spoon, lay up behind the hole. Going to try that if it doesn't go well I'll cut it out

 

[ktmoutfront]

Yep. It pushes the heat out and will not weld.

 

[diesel4me]

I've used brazing rod to fill in holes like those but you need a torch with a "jewelers tip" and some skill to not just burn the holes much bigger--mig welding that panel would be tough...welded metal re-rusts faster too,as it draws the temper out of it..brazing can be done "cooler" and it wont rust like a weld,but its no fun grinding it down and it takes a lot longer..

A repair panel would be a better option probably..once a oem panel looks like this not much you do to fix it will last for more than a couple years...

 

[JoshHefnerX]

I had a bunch of that on both floorboards. A few spots were patches, a few I just tacked up.

 

[Wes Harden]

Going to try to tack them up I have copper to put under. I'm going to move around to each side of floor board to spread out the heat, blow air on it to cool inbetween

 

[Barry Ingram]

If your set on spray can primer look for 2 part epoxy primer, they tend to have better adhesion than typical lacquer rattle cans. I used medallion / rubber seal brand for a small job few years ago. The 2 components mix when can is activated.

 

[Wes Harden]

Monday I hit the driver side with to coats of ospho this is what it looks now.
Wire brush this and try again ?

 

[Wes Harden]

What gauge is the floor board in our late 70's trucks.
I wasn't able to get a patch panel at the wrecking yard today. I will find something I have some scrap. Want to know before I cut out, in case I don't have enough s scrap

 

[1300obo]

16 gauge

 

[Wes Harden]

thanks I measured it with vernier calipers, after I cut the bad stuff out, I got .050" which is a little thinner. 18 gauge ? I found a piece of scrap and made a patch.
will get it welded in tomorrow.

welded up a few holes where the metal around them was good. Got a couple pin holes to fix.

 

[Wes Harden]

Got it done today. Wasn't as difficult as I expected, was having nightmares about make Swiss cheese. One corner I should have trimmed a little more old stuff.
My 1st patch, not ready to do a body panel that will be painted and seen, but this is water tight which is what is needed. Sound deadener and carpet will hide my amateur welds.