Bodywork advice, rear hatch perimeter seal (1 Viewer)

[albert110]

I've gotten to decision time on my first body work project and could use a little guidance. This is the only significant patch of rust I've found on this rig, looks like the combination of dirt/grime and moisture from things being hauled is what caused it.

At first glance I thought it was just dirt when I was doing my initial cleanup but I learned quickly...

This tab that the hatch seal sits on is just a piece of L-shaped sheet spot welded onto the frame. Took me a little while to figure that out, but once I did it was easy work grinding off the spot welds with a 3/8" belt sander

The lucky thing is that the most offensive rust was on the piece I removed, so I've still got the main body completely intact... For now. It does look like the areas around the spot welds did get pretty rusty though. I've been slowly removing material trying not to overdo it and grind through the body in the hopes that I can minimize the damage I do. Here's where I stand with it currently:

So here are my questions:
1. I know that black rust is the most aggressive and I'd like to get rid of as much as possible, but I'm curious how much faith I can put into a few coats of POR-15? I want to do a proper job on this repair, and I'm weighing the decision between the benefit to removing the minimal amount of material versus doing an extensive hack job that I run the risk of really screwing up. FYI, I have not done body work before. I'm excited to have this be my first project because it's going to be covered by trim and carpet, but I still want to do a good job. Should I keep grinding, or cover with POR-15 before I accidentally punch through the sheet metal? Where should I draw the line if I do keep grinding?
2. Does anyone have a suggestion for what approach I should use to replace the tab that the rear hatch seal attaches to? I had originally planned to replace it with an identical looking length of sheet metal using plug welds, but I'm also considering just taking a straight piece of 20ga and T welding it. I am considering the latter approach because it looked to me like moisture had gotten between the two pieces of metal that were spot welded together, so I thought I could avoid repeating that.
I have more questions but they probably depend a lot on the choices regarding the first two issues. Thanks much for any help.

 

[SonnyAK]

I just did a lot of rust repair on our 62 this year and had pretty good luck at my first shot and metal bending and Mig welding. Take your time and do it right the first time so you'll have less issues down the road. I'd make the proper patch piece and weld it in fully (Mig or Tig) and then really seal it up, paint and get the new rubber on. I think you'll be much happier and have more piece of mind if you plan on keeping the rig.

Here's a link to some of the work we did...Maybe it'll help.
Been working on our 62...

 

[albert110]

That's a proper lot of work you did there, I'll be going back over and taking a closer look, thanks!

 

[SonnyAK]

Thanks. It was a lot of work but a lot of fun too. There's definitely a few things I'd do differently. I'm really looking forward to repainting the entire rig eventually.

 

[gregnash]

Sub'd as I have the exact same issue but I have not gotten around to handling it (need a new welder).

Looking at it, since it was plug welded from the factory I would mimic the same. Once everything is installed, painted and done with I would then lay a small line of seam sealer over the upper seam (where you believe rust originated from). This way it keeps things dry inbetween the pieces. Do you know what the measurements for the L portion is? Meaning do you know how high it goes up form the bottom of the body lip (right above the black grommet and wire) to where the actual L bend is? And how far does the L come out?

 

[gregnash]

Any update? @albert110

 

[albert110]

Still getting my ducks in a row here, need to upgrade my welding rig if I'm going to weld in a patch.
I can tell you I measured the L portion is 16mm on both sides. Will update once I get a chance to start doing some cutting in the next week or so

 

[gregnash]

@albert110 Ok so it is like 1/2" piece of L-bracket steel. Good to know. Like I said, I have the same exact issue and want to get it resolved so I can actually have my rear tailgate seal properly. I was assuming that the piece was part of the rear body and I would end up having to replace a whole big section of the body, which was part of the reason I haven't really looked into what was going on. But this helps IMMENSELY!!

 

[albert110]

Yup, I thought the exact same thing, I actually spent a bunch of time grinding the lip down before I took the time to pick away some of the sealant and understand how it was attached, big relief.

 

[albert110]

Well this took a bit longer than I planned... I ended up using this project as an excuse to outfit the shop with all the tools I would need to get the job done, and since this is my first body work / metal working / welding project, I had a lot to assemble. Step one was to bend the bracket. I ended up having to make the piece out of three separate strips that I plug welded together. Isn't the prettiest thing but it'll be covered by weatherstripping so I'm not too concerned.

Next step: Design an incredibly advanced jig to hold the piece in place for welding. I forgot to take a picture, but I should note I decided to keep the original body panel intact, so I took off as much rust as I could with muriatic acid, then gave it a couple coats of por-15. I mocked up the piece, and marked where the plug welds were going to go then ground it back down to bare metal.

My welder accidentally got knocked to the wrong setting so I wasted a bit of metal on the first two or three welds but once I got it set right I was able to bang them out without any issue. I'm hooked, this has been a lot of fun

After cleaning up the welds and filing any burrs off I gave it a few coats of automotive primer. I figure I'm going to do a full repaint sometime soon, and you can't see this part of the body when it's all put together, so my plan is to leave it as is for now.

So here it is, last steps will be filling gaps with seam sealer and putting everything back together. Thanks for everyone's help on here, this was a super gratifying project and along the way I got to pick up a couple of new skills and new toys for the shop.

 

[gregnash]

Damn that looks good... So you used 5/8" side steel for the lip correct? I have to do the exact same thing and need to get it done soon. Looks like a fun little weekend project.

 

[albert110]

Damn that looks good... So you used 5/8" side steel for the lip correct? I have to do the exact same thing and need to get it done soon. Looks like a fun little weekend project.

Thanks! Yup, 5/8" a side is what I measured.

 

[NookShneer]

@red66toy you taking notes?

 

[red66toy]

@red66toy you taking notes?

Hahaha, I did notice this thread! Definitely going to be on the list for the paint/body guy to do... I have no skills to pull this off myself.
Awesome that it can be replaced without having to hack out the rear sill! Great work @albert110

 

[gregnash]

@albert110 Did you use a spot weld cutter bit to cut out the spot welders or did you just grind through them. Debating if I actually want to purchase a spot weld drillbit set.

 

[albert110]

I saw a video on YouTube of a body shop using one of these mini belt sanders to remove spot welds. It worked perfectly, fast enough that I didn't get bored but not so fast that I risked overdoing it and grinding through the body panel. I highly recommend.

 

[gregnash]

Yeah I saw a video where the guy used a thick grinding disc on a die grinder and basically ground through the spot welds then used and air chisel to pull the metal off.

 

[mattressking]

You've just made my day with that discovery. When I pulled the weatherstripping off from the hatch after I bought my truck to inspect, I found the early stages of rust on the edge of the L bracket that the stripping locks onto. Knowing this makes the replacement much less concerning since it is just spot welded onto the floor/rear channel.


Now come down and do mine!