The Stovebolt Site Forums The Parking Lot '60-'66 Trucks Patching Rusted Out Roof Panel

I'm not sure if this thread should be here or in the paint and body forum, so please move it if it is not in the appropriate location. I am replacing the cab on my '63 C-10, and the replacement cab has one rust area that has me a bit concerned - the panel above the windshield on the inside (that the mirror and visors mount to). This area is one of very few that is intact on my old cab, which is somewhat surprising. Not being experienced in body work, I am not sure what the best way to patch this area would be, although no matter what I do I should be able to use the panel from the old cab. The obvious patching method would be to cut out just the rusted area (a strip about an inch and a half wide across most of the windshield) and weld in the good metal from the other cab. However, this seems like it would be very difficult to make look good, and it is a very visible area, so I am wondering about the feasibility of replacing the panel as a whole by cutting it near the seams where it was spot welded together at the factory. The seams I am talking about are inside at the top of the front door pillars, and the one that runs the width of the cab a few inches above the rear window, also on the inside. Another possibility I had thought of would be to replace the entire roof, but it sounds like a major headache to get everything lined up correctly, plus the fact that the outer skin on the old cab has some fairly major dents in it. I am sure many of you have repaired this area before, since it is a common place for these cabs to rust, so any experiences/thoughts/suggestions would be most appreciated

Thanks in advance

You have your hands full cedric. I am not sure what to suggest. I will see of the replys you get here, but I may move this to the body shop forum tomorrow.

Personally, I would cut out as little as possible. Get the joints between the cab and patch piece as close as possible and carefully weld it in. TIG or oxy-acetylene process would be preferred. Good luck.

The area of rust you are dealing with tells me that water has found a way inside the roof somewhere. Carefully inspect the roof for any holes where the roof meets the drip rail.
I am not an expert on body panel repair. However, I have looked at enough of these trucks to know that rust in that area can be more extensive than what is evident on first inspection.
For me, the biggest obstacle to getting it done is overcoming the fear that I will fail. If you can shape metal and have a decent welder and a few simple tools, then I am sure you will be able to get it done. Take lots of pictures and pay attention to compound curves.

I agree with the above posters mostly. The first rule is only replace what is rusted, With a little margin. If that is more than one piece, probably better than one long piece. The donor cab piece is perfect for this. Some shape, same thickness. No custom shaping needed. I assume the windshield is removed. Can't operate with that in. The idea of removing at the seams, a bigger piece, making your own piece, will lead to a nightmare. There are two walls, inner and outer. You will want to be VERY CAREFUL about warpage. You will warp some but use the air cooling method not water. Any time there are bends or curves or dimples on a piece, it will warp less than a flat piece. Go slow. It will grind and you will filler and sand smooth just like any other repair. Don't know why you say it won't look good.

I too am very concerned about why it leaked at that point and only inside. I am hoping it was the windshield rubber leaking. If you are sure there were not rust holes above or previous owner drilled and plugged holes for lights, then it's probably the rubber.

Also sometimes when you sand down to metal just before cutting out the section(s), you will find more than you thought. It is OK to fill small pit holes with glass reinforced filler on the inside of cab. It's all cosmetic in there. No moisture except condensation. Don't mess with the pinch weld that the windshield rubber fits on or mess with the windshield opening itself.

I hope you mean rusted thru, not rusted or surface rust, You don't say the degree of damage. Try NOT to have one long piece.

Cut pieces off the old cab in various spots or cut slits with a 1/16 blade and practice, practice, practice to get the right settings and build your technique. Be sure to sand down to bare metal in all areas to be welded and sand a spot for the ground clamp. In this case you can not back up the weld with copper so if you blow thru, you will be in slight trouble. Even experienced welders blow thru on thin sheet metal. That is the only scary part of this. That is a tough place for a beginner. Your "position" will not be optimum.

You will always have a piece to practice on when doing patching. The piece you cut out. Set welder voltage to chart for that thickness metal and wire size used. Set speed on real low. Start practice weld while turning up speed to hear a sizzle/cracking/buzzing/bacon fry sound. Then your done with set up. Most times it's better to set voltage a little higher than chart and slightly vary the stick-out to adjust. I have learned a few more things about sheet metal welding if you need any help.

I think I have a good explanation for how water got into the roof, it is a big truck cab that had clearance lights, or a least what was left of them. the lenses were missing, the bases were almost totally rusted away, and the seals were badly dry rotted. I had originally thought that the most likely culprit was a mouse nest, but when a couple of you mentioned water getting into the roof I thought about the clearance lights.

The rust could probably be patched the conventional way with a few smaller pieces, but I am stiil thinking the easiest way to change it over would be to transfer the whole roof panel over from the other cab, since there are no shaping or fitment issues anyway, and It seems like it would be easier to hide the welds in the factory seams.Since I started this thread, i have done a little more research and found out that you can remove the roof panel by cutting out the spot welds in the drip rail. My thinking was that I could take this procedure one step further a remove the inner roof panel as well, and then reassemble it all with the good inner panel from the old cab. I may be dreaming, but it doesn't sound that hard to me, and to some one with the amount of welding (very little) and body work (none) experience I have it seems less daunting than welding and grinding seams in a very visible area. It also has the added advantage of allowing me to clean up any potential problems lurking in the roof. Unless I here from you all that this is an absolutely horrible idea, I am going to try to dissasemble my old cab in this way, So that I can get a better feel for how well this might work.

It may sound like i am aswering all of my own questions here, but I am just trying to organize my thoughts a little better. I was in a hurry when I wrote the first post, and it wasn't as clear as it could have been. I am still very open to advice and suggestions. I may very well end up using the conventional method, welding small patches and using a grinder and bondo to clean it up, but I want to make sure I have looked at all the options.

Disassemble of old cab is a good idea. It will tell you if your plan will work. It also does not destroy anything if you decide to patch using the old cab. I would think that patch is better for me, but I have not examined the whole picture like you can having the parts right there. Get a good quality spot weld cutter/drill. You will develop a technique as you go and then get better and faster.

A possible risk I see is with the wrap around windshield. They are very hard to install. I've done a few 55-59. There is a dimensional tolerance issue because of tolerance of the glass and tolerances of the opening. Sometimes causes big headaches. If your effort involves the opening, it is possible that you will change the size and shape of the opening. Doesn't take much for a wrap around style. 63 is the last year for those. The 64 and up flat windshield is way easier. You could get all done and windshield does not fit. Are you getting a new windshield or using the old? I realize you are changing cabs and may or may not be matching windshield glass to it's mate. The point is that you do not want to end up with a windshield opening that is beyond the factory tolerances. The opening is impossible to measure so you won't know. If at least one half of the windshield pinch weld stays stationary, you should be OK. Just try to figure out how the factory positioned the pieces before welding. Maybe they have location features built in. If they used jig fixtures, that's a problem. That opening HAD TO be within factory tolerances so rubber and windshield would go in every time, no leaks. A big windshield and a small opening and vice versa.

Good to know about the windshield opening. Hopefully I will be able to leave the bottom of the visor-like overhang in place, and hopefully that will help preserve the dimensions. I haven't looked into it yet but does anyone know where I might find out what the factory tolerances are? I guess I could always just measure the opening as it is now and just make sure it stays the same, but it would be nice to have a range. I might be able to weld in a couple of braces to help maintain the opening as well.

I currently have 3 NOS windshields, including the one from this cab, and I will use the best one, which may very well be the one from this cab

I'm sorry, bartamos, somehow I read you post 3 times without seeing the part about it being impossible to measure. Nevermind about what the factory tolerances are, and the idea of maintaining the current measurement.

Pix from start to midway would be nice. Carry on.

Somewhere I read that moisture (rain, snow, mud) that gets in the cab (from shoes, window left open, etc.) evaporates and rises to the roof between the two panels and condenses there, accumulating in the cavity above the windshield.

I guess that makes sense.

Mice are notorious for urinating in these areas.

They urinate upside down? Above the windshield?

Little known fact. Mice have absolutely no bladder control. They pee continuously, So wherever they go, there's mouse urine.