The rockers on my old Ford were rotten and disgusting. People couldn't exit the car without gnarly rust taking a bite out of their calf. So, for the sake of my friend's legs, I cut out the rust and welded in fresh cold steel. Here's how I did it.
I bought some patch panels from Dennis Carpenter. They were 60 bucks for a pair plus shipping; 30 bucks a side isn't too bad to get rid of that nasty tin worm.
They seemed a little thinner than the stock steel, but they were good quality and didn't and ground down my beads. After grinding I welded up any pinholes I found. Full Disclosure, I don't have a lot of experience welding and I leave plenty of pinholes.
After the rocker to the rear of the door was sorted out, I set about the task of fitting the new rocker beneath the door.
So I broke out the clamps and did a little creative cutting to get this thing to fit right.
I used my air punch to pop some holes along the bottom so I could plug weld the outer rocker to the inner rocker.
This works pretty well but welding upside down through a tiny hole is challenging. I made sure to move my clamp along as I welded to ensure the two pieces were making good contact.
First I scuffed the inside of the panel with red Scotch-brite to scratch the surface and create a mechanical bond between the steel and the primer.
I masked off the holes I punched so they'd still be clean enough to weld.
I coated the inside of the rocker panel with Self-Etching primer and then painted it with VHT's Chassis and Roll Bar paint.
I like the Dupli-Color primer because I know that when I spray it on it's biting into the metal, and isn't going anywhere.
It dries quickly which means I don't have to wait all day to get my next coat on or to paint over it.
I chose the VHT product for this application based on previous experience with the product.
They advertise this as an Epoxy product which means it dries hard and remains durable. It's impervious to water and resists scratching.
I wanted something resilient inside the rocker to prevent future rust.
Here it is all welded in. There's still a tiny rectangular hole just behind the door that needs to be filled where I cut my patch too small but it shouldn't be too much trouble to fix.
It's not perfect. The fit under the door could be a little better, and behind the door needs some hammer and dolly work before I start with body filler. I want to see if I can improve the gap at the back of the panel too. But hey, it's my first try and it's a lot better than all the nasty rust that was there before.
For now I'm going to scuff it, prime it, and hit it with some rattle can paint which will keep the rust off until it comes time for body work and filler. Stay tuned!