[Ravenbar]

I'm working on a rust repair/strengthening of my DD Jeep WJ. I've found a couple pinholes in the frame rail above the rear lower control arm mount. I've also found a significant amount inside the framerails in that section. No replacement sections are available that I've been able to find.

My repair plan is twofold. One, remove and treat as much rust inside the framerails as I can. Second, install frame stiffeners from the front LCA mounts to behind the rear coil spring buckets.

To accomplish this, I've sourced IRO frame stiffeners for the center(front LCA mount to rear LCA mount) and Trail Forged rear wheel well frame stiffeners for the rear wheel well area. That leaves an 1'-2' section, in between the sets, where a body web usually exists(removed due to rust and prepping for replacing it and replacing the rockers.) I'll be making my own stiffeners to cover this section.

My big concern is that the IRO parts are 3/16" steel and the Trail Forged parts and parts I'll be making are 1/8" plate. That leaves the change in thickness and likely stress riser at the worst point, as that's the part I'm attempting to strengthen.

 

[222Doc]

i would not make things like arm mounts from 1/8. Factory does but they stamp a shape into it that makes the 1/8 stiffer. If you make the same out of 1/8 but its flat it will bend rather easy.

 

[Ravenbar]

i would not make things like arm mounts from 1/8. Factory does but they stamp a shape into it that makes the 1/8 stiffer. If you make the same out of 1/8 but its flat it will bend rather easy.

Not making the arm mounts themselves at all. I'll be plating the outside and bottom of the frame l around the existing mounts. The framerail is deteriorating from the inside, from the joint just behind the the transfer case, up to just behind the the control arm mount.

WJ's are know for rotting out in this area, with the rear LCA mount cracking out of the frame rail. By strengthening the outside of the framerails, then removing the deterioration on the inside, I hope to avoid that happening.

 

[CJ7-Tim]

I would not worry about the metal thickness transition causing a stress riser if the welds are good. If you are concerned, make fish plates to cover the joint and consider using "runoff" or "pigtail" welds on them.

 

[Ravenbar]

I would not worry about the metal thickness transition causing a stress riser if the welds are good. If you are concerned, make fish plates to cover the joint and consider using "runoff" or "pigtail" welds on them.

I fully intend on expect very sketchy welds. I can make beautiful welds and on the same joint make welds that are an insult to bird crap, doing the exact same thing. Been spending lots of time practicing lately and haven;t found anything I can tweak that makes it more consistent. Today I rebuilt the section of the body that hangs down behind the passengers side tire. I had thin to thick joints(factory metal was 18-10ga, I was using ~14ga to replace, as it's what I have a stock of. put down some beautiful welds, then right back to crap, on the same joint.