How Can I fix this rust on my '85 J10?

[cavalier]

So, my J10 has two rust spots that have chewed through the metal, and the rest is really clean.

So I'm wondering how I should go about addressing them. Here are some pics:

Back of cab:

http://i.kinja-img.com/gawker-media/...1137295786.png

Door Jamb:

http://i.kinja-img.com/gawker-media/...1182401450.png

Any suggestions?

[pyro]

Grind down to see how bad they really are. Door jamb looks like it can be repaired with a new rocker panel. Assuming it doesn't go too far up. The rear window may be a bit more involved. You may end up having to recreate a panel for it and work from there. To repair correctly both require cutting out old and patching in new panels.

[cavalier]

Originally Posted by pyro

Grind down to see how bad they really are. Door jamb looks like it can be repaired with a new rocker panel. Assuming it doesn't go too far up. The rear window may be a bit more involved. You may end up having to recreate a panel for it and work from there. To repair correctly both require cutting out old and patching in new panels.

I've seen those outer rocker panels, but I don't think those will do it, as they don't include that round curve where the rust is.

[tgreese]

Under the window, you may get away with spot-blasting the rust and repainting. Depends on how thin the steel is. Don't get your hopes up - the steel is usually in worse shape than it appears before you remove the rust.

The door jamb is pretty bad - if you want to fix it right, you'll need to cut out the rusted area and weld in new steel.

Do you have air? I would get one of these and a bag of media and go at it. http://www.tptools.com/Hand-Held-Abrasive-Blasters.html

[joe]

You're not going to know how much metal is going to need to be cut out and replaced till you dig into it. Your new replacement metal is only going to be as good as the old steel it is welded to. The curved door jamb is going to take some custom creativity (time). The cab back don't look good either. I would also expect the entire lip the window gasket attaches to will need to be replaced. If it's as bad as it looks from here, I'd also closely inspect/probe the cab mounts behind the seat, the cab corners and top of the A-pillars. If you need a shop to do it right, it's going to be all custom work. Read: labor intensive/expensive. No sense spending a lot of money on part of it just to have other parts go south soon after. Money wise I think I'd be looking for a good donor cab outside the rust. Even after shipping it's going to be cheaper than shop time. I used to live in Detroit and feel your pain fighting the rust demon.

[8man]

Can you weld or do you have access to someone who does? That's the first question to answer. If you can't and/or don't, this is not so easy a fix.

If the answer is yes, then get out the grinder and a wire wheel. Cheap if you don't have one. Use the wire wheel to remove paint/rust until you get to good metal. When you think you are at good metal, use a small bladed screwdriver to poke around to see if you have good metal or more rust. Then you can determine how much rust you have and what will need to be removed and replaced.

As stated above, your patch will ONLY be as good as the metal you are working with, so get rid of the rust first.

Over on Garage Journal.com you can look up MP&C and their thread on rust patch to see how it is done. Practice on a throw away piece of metal, and then patch the rust.

Good luck.

[babywag]

Yep, might be cheaper in long run to just get a rust free cab if you're going to pay someone to do this work?

Sanding/Grinding is not going to cut it, for GOOD rust repairs you need to blast the rust clean, then cut out the damaged areas leaving good metal for the patch panels.

What are your goals for this? What's your budget? What's your skill set, and do you have the tools required?

Not trying to discourage you, but having lived in the rust belt, and worked as an auto body tech, seen and dealt with more rust than I care to recall.
It's expensive time consuming work, and it costs $$ for a shop.
It can be done DIY style, but you need to have the time/tools/etc. to do it right or it'll just come back.

[serehill]

This truck is in worse shape than it looks like the scuff plate has even been move back to cover some of this. I believe your pictures are just the surface tip of the iceberg meaning this is only 20% of what is going on. I would check the frame & everything very closely. I'd do an objective analysis of the entire vehicle before even starting. The back of the cab started under the window seal & from experience I can tell you is probably not good. I think it safe to assume you do not have the expertise to fix this or you would not be asking how to fix it!!!!!!! Don't let anyone fool you cutting & welding sheet metal back together is very tedious process. Understanding the welding process tack welding to keep the metal from warping is not some thing you just pick up. Your level you want to take this to also has a key part to play in this. I'm assuming you're wanting to make it nice. If that is the case I would find a southern rig & have it shipped there fro what it's going to take to patch this together.
Sorry just laying out the facts. You would be surprised of the number of failed project this type of work causes

[threepiece]

Whichever route you choose be sure that a grinder is never used to remove the rust. Grinders do not discriminate, they will remove more of the precious metal you are trying to save in a few seconds than rust will in a few years.

[TexasJ10]

Once you determine the extent of the rocker rust, and assuming your entire cab isn't a mess, some wrecking yards are more than happy to cut a section out of a wag or j truck that you can weld in. It is a lot easier than dealing with the curves and thin metal when repairing it. Sometimes what they ask for the section seems high, but when you consider the time it will take to repair it is a bargain.