Cab corners

[Matt_50]

I've been patching up the cab lately and I started cleaning up my driver side cab corner today. Both sides need to be done and when I feel inside the inner is rusted too.

I've been trying to find a good walk through for the corners. Something detailed and with good pictures before I start cutting it up. Are the inner and outer welded together? Is there any reason I shouldn't put in corners on the inside to have a flat floor instead of the pockets?

[MARTINSR]

I don't have a walk through for you, but basically you would replace one at a time the inside first then the outside. But it's pretty straight forward, you buy the outside and then the inside you could make pretty easy.

Brian

[Matt_50]

Are the two connected or welded at the bottom?

[8man]

From what I could tell they were spot welded at the bottom.

I cut the outer smaller than the replacement patch to leave me plenty of room to make the replacement outer patch fit. Once the outer was cut away I could see the inner and I just replaced as much as needed to be replaced there. Then I fit the outer, welded up at the cab joint and then spot welded the bottom.

Oh, I left out the weld through primer on all the inside I could get to before welding the outer over the inner.

[Matt_50]

Ok so... I cut out rusted area. Repair the inner. Place new outer patch on outside and trace from inside the cab to outline the cut. Cut it, weld it, spot weld to inner.

[8man]

Pretty much. The time consuming part for me was the fitment of the outer cab corner. I tried to check and double check fitment and lines before I cut too much off of either the cab or the patch.

Also, if you are using less than one cab corner patch panel by cutting it short, you can always cut it out and do it again with another patch panel if you need to.

[e015475]

There's a guy on another board doing some panel repair on an AD. Not much explanation but quite a few photos.........

https://talk.classicparts.com/thread...s.13338/page-6

[b-mac]

Weld slooowly.

You could make the floor flat but there would be nothing to support that can corner. You need the inner.

I have pics of when I did it, but they are on my laptop. Can get to you tomorrow.

[Matt_50]

Great link! I like it when guys post a lot of pics. 8man the more pictures the better. Pictures and YouTube and just trial and error are the only way I learn lol

[e015475]

There's a cracker-jack metal fabricator that's posted a bunch of tutorials on the GarageJournal on welding in patch panels. It isn't specific to cab corners, but he spends a lot of time explaining the finer points of fitting, welding and finishing patch panels.

His name is Robert McCartney (or something close) and calls his shop MP&C. I think he's pretty good at teaching the process. Check him out here-

https://www.garagejournal.com/forum/...d.php?t=182565

[e015475]

The number of pages in the previous link is something like 139

It's kind of like asking 'what time is it?' and being told how to make a watch.

(I've read it all, and most of it 2-3 times, but that's just me.)

If you want something more to the point try this one-

https://garagejournal.com/forum/showthread.php?t=53534

[oldman3]

Originally Posted by e015475

His name is Robert McCartney (or something close) and calls his shop MP&C. I think he's pretty good at teaching the process.

e015475, Robert also shows that build on this site, it's it Alternate Tinkings and the thread is this http://67-72chevytrucks.com/vboard/s...d.php?t=564201. Jim

[8man]

Robert really knows his stuff and teaches well. I have read his thread too and really shows a lot. Doing is the way to learn, but reading or watching really helps. If you do it the way Robert shows, it'll turn out.

When welding body panels, I use the ESAB EZ grind in 0.23. Robert suggested that to me. It works better, also he uses a cut off disc to reduce the proud part of the weld. Works well if you take your time and do it slowly as stated above.

[Matt_50]

I like to get a little reading in each day and that link is a great source of info. Next week I hope to order what I need, in the mean time I'm doing other smaller repairs. Driver side lower cowl was a small patch, found an antenna? hole on the driver side below corner window. Ive also got a couple patches to do in the inner cowl area.. well the area between the inner and outer.

I'm a little broke but... I was at Lowe's and I was looking at their small mig welder. What smaller welders would be better for sheet metal than this flux core I'm using now? I'm getting better at it andbim getting less burn through, but man do I have to go slow and still redo spots.

[b-mac]

Get a mig. You'll never regret it. Spend as much as you can.

My Eastwood 175 is nice, and the price was right. But if I had it to do again, I would have spent even more.

Between that and my plasma cutter, I feel like I could build ANYTHING!

Also, I purchased my gas bottle at an Ag supply store. Getting it refilled is inexpensive. I don't use it nearly enough to justify one of those monthly lease programs.

[Matt_50]

Man, I wish I had a plasma cutter too.

[b-mac]

Look at Simadre Tech, cheap foreign junk, but mine has been working like a champ for 5 years now.

It's initial test was cutting up the original 49 fame into pieces I could haul to the dump in a small truck bed.

Only downside is I haven't found a competitors consumables that work, but it's cheap enough to buy a few dozen online.

On the Eastwood welder, Lincoln consumables work perfectly.

[OrrieG]

Look at my thread starting with this link. I had to make my inners, they are now repoped. Expect to possibly have to pie cut and massage aftermarket metal. http://67-72chevytrucks.com/vboard/s...2&postcount=47

Later on in the build thread I did the lower door hinge pockets too.

[Matt_50]

Ok guys, my corners should be here Tuesday. I did some more prep and I cut just the rust area out of passenger side. I'm pretty sure I can patch/fix the inner. I can then use it as a reference for driver side.

I may have mentioned I have used a flux core little welder for everything so far. I know it would be ideal to have a better welder and be able to use it... but I don't.

I plan to go extremely slow. I would like some advice on a couple of things.

1st, to help prevent warping. Can I use a heat sink? Magnets maybe? Does that work?

2nd, I'm getting better, but I do get some burn through with this welder. Since this is in a nice hidden little hole and it should be safe from the outside, is it ok to have a strip of metal on the inside across the back of the weld?

[8man]

I have read on Garage Journal a post by MP&C on "how to weld thin metal", specifically what you are trying to weld.

He uses a tack about every 5" +/-. Stops and uses a cutting disc to remove the proud part of the weld. Then when it is smooth like he likes it, he does another tack next to the last over and over until the entire weld line is complete.

Going slow like this will help control heat. Another guy keeps his air hose next to him when doing this. Every once in a while he shoots the weld area with air if he thinks it is getting too warm for his liking.

The area you are welding should be a little more forgiving than say when you replace the bottom of the door and have a long run on a straight piece of sheet. However, you are wise to be concerned about the heat build up and should take precautions.

Where you are welding, you have had a rust through. If you look inside, you may see that there is other metal that has pitted over the years. This pitted metal, when trying to weld may give you a blow out even if all else is set right. I can't speak to what others do, but I slow way down on the blow out, let it cool and start spot welding it in until I fill it back up.

You are right about the gas versus the flux welding. It would be better, but you can do it if you take your time and watch closely. If you think it is getting too warm, cool it down, or stop for a little bit. Patience is your friend when doing this.

If you want to be really cool, check out oxy/acetylene welding. THAT is the way to go, it is at least as good as MIG, some say better.

Now, if you think I'm doing all this, you would be wrong. I am trying. I am getting better at the patience and taking my time and keeping to the spot welds and working each then doing it all again. I can say that when I do, I get much better results.

That's what I think. I'm sure others will have their input as well.

[b-mac]

Yes to your last question. In fact, it might be easier to use a lap weld, rather than a butt, with that flux welder. If you could find a way to create the lap joint. My HF hole punch does a pretty damn good job.
Use the part you cut off as your pattern on the new metal. If your going to do the lap, measure 3/4" more than that. Masking tape will make this gap for you easily.
Lately I've been sheet-metal screwing new metal to old and cutting both at the same time.

You could definitely put a little strip of metal behind there too. That's basically how they do adhesive patches.
If you do that (and maybe if you don't) you might consider some weld through primer on the metal that the welds will trap from paint.

You can use magnets to hold everything, but don't weld directly one them. Heat causes them to lose magnetism.
You can hold copper to the back side of your weld to prevent burn through...and you can't weld to it. Smashed copper pipe will work, but you can melt it.

I welded the first half of my cab with a flux core. It can be done.

[Matt_50]

Thanks guys, ok I think I'll use a strip behind the joint. Spray it with weld through primer too. I'll also try this every so many inches and then make smooth and go again.

Maybe the cutting and making it smooth between each tack will help keep me from over heating. I've noticed if I use cut off wheel vs grinding wheel it's not as hot.

I'll post back after I start to repair the inner.

[Matt_50]

Got my cab corners in. These are very big patches. Do any of you guys ever have to use the whole patch? I'm going to get some then take, something I can wrap and make curve with so I can cut a better line on my cab. Just a tiny bit above current cut. And I think I'll use a piece of the leftovers from the new corner as my backing piece.

[GreasyLikeaBurger]

Originally Posted by Matt_50

Got my cab corners in. These are very big patches. Do any of you guys ever have to use the whole patch? I'm going to get some then take, something I can wrap and make curve with so I can cut a better line on my cab. Just a tiny bit above current cut. And I think I'll use a piece of the leftovers from the new corner as my backing piece.

I would suggest before you just start going ham on the sheet metal, watch a few videos of guys doing it. On youtube I have followed gibson63, he has a lot of videos of doing all the repairs and restoration of old chevys. Yes they are not our model of truck but the repairs are basically the same.

https://www.youtube.com/watch?v=6w2H6c6W1s8

also there is MobileHotRodRepair - they are his older videos, kind of low budget. But you can get what he is saying by his work. He also does tech videos for Brothers Trucks and has been doing it for a long time. He also on instagram and posts up videos regularly on there.

https://www.youtube.com/user/mobilehotrodrepair/videos

[8man]

I didn't use the entire patch. I used only a small part, just enough to cover the rusted out area.

I cut out the rust first. Checked the metal that was left to hope it was solid enough. Then I did a rough cut on the panel to bring it down "closer" to the right size. I was told to use tin snips to do the final trimming and it worked very well. I kept trimming on both the cab and the patch, and test fitting them together until I finally got the patch to mate to the cab the way I wanted. I had more time in cutting and trimming to make the patch match the cab than I did in welding.

On one side I actually cut the patch down some, used vice grips to hold it to the cab and used a cut off wheel to cut both the cab and the patch together at the same time. This seemed to work, but I like the fit of cutting and trimming to make it just so.

I started with the smaller area than I needed so that IF I messed up I could cut it all out, get another patch and start over.

I like Gibson63 videos and have watched a bunch. There are others, but you have to figure out what works for you.