Rat repair.

[Vic1947]

What I do is take a grinder with a flap disk and carefully grind the edge down perpendicular to the door skin until you see all three edges... outer skin, inner structure and folded over metal strip. Don't worry about the spot welds, you can use a thin kerf wheel on the grinder and remove enough metal around the spot to loosen the strip that's left behind.

You can go up the front and back edges as much or as little as you need. This will free a strip on the door skin that can be trimmed with the thin kerf cutting wheel or snips... if you're really into self abuse. Trim the patch panel to match and leave about a half inch extra where it meets the trimmed edge of the door skin. If you don't have an offset flanging tool, there's an air powered one available from Harbor Freight or manual ones from various sources.

There are clamps available that grip each side of an unflanged cut, but sometimes the weld draws the gap together and makes it very difficult to remove the thin blade. I prefer to flange the patches so I'm not trying to fill a gap on long sections. The extra material helps reduce warping, although low heat and patience are still needed.

Don't assume the GEM product will get in all the tight places. Last thing you want is rust popping back 6 months to a year from now.

[swamp rat]

Well the destruction has begun, naturally I find some cancer I didn't see before. Now I'm at the same crossroads I was at with the other door, I think I should go up a little higher to get past the rust along the seam's but with the last door the higher I went the more the door pulled in under stress, really hoping this won't happen again. I think what I'll do is shave the sides up each side little by little before I just trim the skin off to see how the skin responds, hopefully no stress in the door this time.

So out fell one of the vent window screw bushings, I cant remember if I ever removed the screws and lost one and replaced it or if someone at the factory might have dropped it.....

[swamp rat]

Not a lot getting done the last week, too many things going on....

I trimmed up the sides little by little and am very happy to see that this door skin is not caving in like the driver side the sides are now past where the rust stops and I had to trip an additional inch off the lower part to remove the remainder surface rust on the skin.

On the inner panel flange I'm debating on buying a lower repair panel and replacing pretty much the whole flange this time, That would mean making a run to Olympia for th inner lower. I'm looking for an easy way to work this.

[Vic1947]

Originally Posted by swamp rat

... I'm looking for an easy way to work this.

If you decide to replace the inner panel, easy will go out the window. They don't fit very well, IMO. Yours is not too terribly bad and could be salvaged with GEM, epoxy and self etch primer. When I did mine, the inner panels I bought were wrinkled and fit poorly. I think you'll more than double your work if you replace them. The key to using what you have is to seal out any future moisture to prevent corrosion. As you can see, the rot already has a head start, so if moisture is allowed to creep back in, it will come back very fast.

[swamp rat]

Originally Posted by Vic1947

If you decide to replace the inner panel, easy will go out the window. They don't fit very well, IMO. Yours is not too terribly bad and could be salvaged with GEM, epoxy and self etch primer. When I did mine, the inner panels I bought were wrinkled and fit poorly. I think you'll more than double your work if you replace them. The key to using what you have is to seal out any future moisture to prevent corrosion. As you can see, the rot already has a head start, so if moisture is allowed to creep back in, it will come back very fast.

Yea, I'm just looking at the flanges themselves and not the whole inner section, my main concern is the thinning of the metal and being able to spot weld the skin to it after folding the skin over, the triangle piece is bad and thin enough that like the other door I think it would be pretty difficult to weld in a small patch. I will say that of all this rust repair I think I hate the doors the most. LOL!

[rgunlock]

I'm no expert on this Mike, so no advise on how to handle the door. You'll get it licked and look back knowing most of your other repairs shouldn't seem too daunting.

[swamp rat]

Originally Posted by Vic1947

If you decide to replace the inner panel, easy will go out the window. They don't fit very well, IMO. Yours is not too terribly bad and could be salvaged with GEM, epoxy and self etch primer. When I did mine, the inner panels I bought were wrinkled and fit poorly. I think you'll more than double your work if you replace them. The key to using what you have is to seal out any future moisture to prevent corrosion. As you can see, the rot already has a head start, so if moisture is allowed to creep back in, it will come back very fast.

So lack of knowledge shine's through... I made the drive to Olympia after work to buy an inner repair panel thinking that they had that triangular stiffening raised area on the forward flange formed in to the repair panel, Nope! I thought it would save me some time and effort to cut that off and use it, oh well..

On the last door I think I used a router bit and made a wooden die and hammered the shape out of flat stock then used a portion of it, was not perfect but it helped stiffen the flange, that may be a repeat in my near future but I need to do some spot blasting to really see what I have to work with..

[swamp rat]

Originally Posted by rgunlock

I'm no expert on this Mike, so no advise on how to handle the door. You'll get it licked and look back knowing most of your other repairs shouldn't seem too daunting.

Thanks for the vote of confidence! And glad your high and dry!

[swamp rat]

First idea, just cut the raised part put and use a flat plate, quick and easy, may not be as ridged as stock.

Second idea: Roughed out a triangle, can weld it to the plate after I form the contour, I could drill some holes in the plate to allow it to breathe from the underside. Or pending the results of sand blasting I may get away with using only part of the triangle?

Guess I'll find out soon enough.

[swamp rat]

Blasted the flange and its a bit worse than expected, the flange is pretty thin so not sure if I'm going to be able to spot weld the holes closed, guess I can try and see.

Can anyone tell me what the "official" term is for the black deposits the rust leaves behind? that stuff is tough and didn't want to just blast away.

[Vic1947]

Originally Posted by swamp rat

... Can anyone tell me what the "official" term is for the black deposits the rust leaves behind? that stuff is tough and didn't want to just blast away.

It's just iron oxide (rust) formed in a low oxygen environment.

[swamp rat]

Copper, It does a body good! I shaped a couple contours in my copper backing plate and clamped it to the flange and with pretty low heat I succeeded in filling the holes, not real pretty but its good enough. I gotta admit I wasn't sure I could get it done but glad I didn't have to cut the flange away.

[7dee2]

Way to go, nice job Mike! So isn't the iron oxide the goal or results of a rust converter and safe to seal when it's in this stage?

[swamp rat]

Originally Posted by 7dee2

Way to go, nice job Mike! So isn't the iron oxide the goal or results of a rust converter and safe to seal when it's in this stage?

Heck Brett, I don't remember the tech term for it anymore, its all become a blur to me LOL!! But I will use the converter and then seal it up with some primer.

[swamp rat]

Ok so I have been quite busy but not all with the truck, my wife is outta town taking care of family business, that leaves me here with all the animals one of which had to go to the vet for 2 days, $850 later..... That and my foot has been killing me to boot.

Also with the predictions of rain on the way I took the time to recover my car covers on Saturday, kind of a pita when your by yourself.

Ok so I have been slowly working on my panel getting it fitted, knowing my luck with under cutting I have been taking my time, I have the spot weld holes drilled on the two folded flanges, flanged the door skin where possible.

This leaves me to the last flange and my current headache, what is it with these replacement panels that they pre fold them 1/4# wider than the door? Naturally flattening that 90 out to refold it takes the contour right out of the skin. I'm thinking the best way to get the skin folded would be to clamp it in place and use a few Cleco's on the overlap, then dolly and hammer the flange over. The other area for concern is the contour of the inner door didn't match the skin contour before I flattened that flange out, the lower part of that triangle seems to have a high spot.

[swamp rat]

Got the skin clecoed on the outer skin flanges and used 4 small clamps to hold the skin in place then started rolling the skin over on the last edge, once I got the lip at 90 degrees I had to break out the shrinker and rework the contour then I finished rolling it over but not tight as I still need to remove it and do some rust proofing and priming.

[swamp rat]

Had to run to the hardware store to buy more paint brushes to apply the GEM rust converter, as I was doing the application the sun came thru the window and with the door upright and upside down I spotted some more pin holes, I got a small light and found a total of about 9 if them, much smaller but there none the less. Now I hope the pin holes can be welded once the GEM has dried up... Tomorrows task.

[bilfman]

Lots of work there! Looking forward to see the finished product!

[Vic1947]

Originally Posted by swamp rat

Had to run to the hardware store to buy more paint brushes to apply the GEM rust converter, as I was doing the application the sun came thru the window and with the door upright and upside down I spotted some more pin holes, I got a small light and found a total of about 9 if them, much smaller but there none the less. Now I hope the pin holes can be welded once the GEM has dried up... Tomorrows task.

I really hate chasing pinholes using a welder... MIG or TIG. Even using a copper spoon to back up the weld, it seems like the pinholes explode into an even larger hole that takes forever to close up. I've been known to thoroughly clean / scuff the backside of the panel and put down a couple of layers of fiberglass cloth or mat to just cover the affected area. Then be sure to brush on a couple of coats of epoxy primer to prevent any moisture from getting between the glass and the metal. As long as you don't need to weld something else in the general vicinity, this is an effective repair that doesn't warp the surrounding metal.

[swamp rat]

Originally Posted by Vic1947

I really hate chasing pinholes using a welder... MIG or TIG. Even using a copper spoon to back up the weld, it seems like the pinholes explode into an even larger hole that takes forever to close up. I've been known to thoroughly clean / scuff the backside of the panel and put down a couple of layers of fiberglass cloth or mat to just cover the affected area. Then be sure to brush on a couple of coats of epoxy primer to prevent any moisture from getting between the glass and the metal. As long as you don't need to weld something else in the general vicinity, this is an effective repair that doesn't warp the surrounding metal.

I came to the conclusion after the 5th hole just as you described that the rest of them were not worth chasing as there so small the primer will cover them up. Did a bit more skuffing on the inside then another coat of Gem.

Do you recommend the K2 primer over the Gen or Metal Etching?

[Vic1947]

Originally Posted by swamp rat

I came to the conclusion after the 5th hole just as you described that the rest of them were not worth chasing as there so small the primer will cover them up. Did a bit more skuffing on the inside then another coat of Gem.

Do you recommend the K2 primer over the Gen or Metal Etching?

I'd use the self etch primer and follow with 2K. I'd be leery of counting on primer to fill pinholes. At a minimum you need something impermeable on the back side to keep the moisture at bay.

[swamp rat]

Ok I chased every last pin hole I could see with a light shining from the back side, what a pita! Recoated everything with GEM and its drying overnight.

Is there a difference between self etching primer and Acid etch primer??? One in the same?

[Vic1947]

Originally Posted by swamp rat

Ok I chased every last pin hole I could see with a light shining from the back side, what a pita! Recoated everything with GEM and its drying overnight.

Is there a difference between self etching primer and Acid etch primer??? One in the same?

I think, generally speaking, acid etch (or wash) primer refers to products like the GEM Rustkiller which is a mild phosphoric acid that converts the rust and helps keep the metal from forming new rust in moderately dry environments. You may also hear the term alodine coating in the same sentence with acid etch primer, although I've personally only seen it applied to aluminum.

Self etch primer usually refers to a coating that cures and has a heavier film build (thickness). Unlike epoxy, it is typically a single stage coating with chemical additives that grip the metal tighter than lacquer or 2K primers. It is a suitable base for most subsequent layers of primers / paints.

Some two part epoxy primers don't adhere well to metal that has been treated with phosphoric acid and has residual iron phosphates on the surface. So if you want to be safe, don't squirt epoxy over the GEM without first wetting the surface with a mild solution of GEM and water, flushing it thoroughly with water and then allowing it to dry for 24 hours. Some epoxies don't care, but I don't have a thumbs up, thumbs down list, so treat them all as if they are sensitive to iron phosphate.

Techniques for prepping bare metal for paint are varied and success depends on what's underneath and what's intended to go on top of the bonding layer. New metal with no history of rust can be treated to a much different regimen than old rusty, pitted metal.

The one thing you can be sure of is that rust is the worst where moisture gets trapped between two layers. We've all seen pictures of old cars in fields that are rusted all over. However, the metal on the exposed surfaces is often in surprisingly good shape. But down at the bottoms of the doors and adjacent to any double walled construction, the rust will have created blisters and gaping holes. So proper metal restoration means not only replacing or neutralizing the rusted metal, but also finding and fixing the source of the rust... which is usually water migrating from somewhere above and collecting in the tight spaces. If you don't address the root cause, you're wasting your time.

[swamp rat]

Off to the slowwwww races. Primer is covered nicely although the camera doesn't show it, taking lots of time with the spotwelds so they cool.

EDIT: I'm about 75% spot welded, 4 more passes not shown in the pic spaced 2" apart and 65% of all spots ground down , this thing is holding shape much better than the last one, its just now starting to show slight pulling, not bad considering I cannot planish the spot welds.

[7dee2]

Really nice work!