Instead of JB weld you may want to use 3M panel bonding adhesive part NO# 8115 it is made for doing that. I use it all the time to do door skins and quater panels on newer cars but have found many uses for that stuff along the way. The 8115 is the strongest product I have ever seen. Just about all OEM manufactures are using this product for there cars. They say it is just as strong as welding in some cases panel bonding ( NOT STRUCTURAL). I have done tests with this product and it holds up to its name 3M.
Just wondering now, anybody know if the jb weld resists corrosion or will water seep on in? i mean it would suck to do this repair over again after the new patch rusts out?
well without reading every post since there is a thousand on this thread, I know that even though it looks fixed, you simply put something over the rust, the rust is still there, and will continue to rust, and will rust out the metal you put in eventually. The good news is tha area needed to be cut out and a patch welded in, and the piece you put on is small so you can simply still do that someday when it needs it again. I like a little rust on a hot rod, adds flavor
Congrats of involving your son in your passion. My son is only 2 so I've got a while to wait yet. On the subject of JB Weld, I love the stuff. Last time I used it was when I converted an FJ HOLDEN PanelVan (I think Americans would say "delivery") into a ute (unibody pick-up?) I used it to join the rear roof section and upper tailgate to rear of cab. I also shaped the "Tonneau Cover" with JB Weld. Here's a pic.:
It is possible to lay real chrome over almost any surface - they use an electrically conductive paint.
I think part of the issue here is that we've all cursed the guy who did a repair like this at some point in our 'project car' lives, I know I have. Mine used expanding foam. I'm also amused by how many people throw around the statement 'get the car on the road' like a car needs all the rust patched to be on the road. You could drive it just fine with that hole in the door until such a time that you had the 3 or so hours it would take to repair that properly. Now you get to spend 2 hours undoing it before you do it. Or whoever buys the car does. And finally, the argument that it's an 80 year old car and that they're getting scarce is just another good reason to repair it correctly, It's made it 80 years - why not give it another 80 by doing actual metal repairs?
For you guys scared of welding, Miller has a welder called the Millermatic 140. Great for the new guy. Flux cored MIG and all you have to set is material thickness (up to 3/16") and wire thickness. Operates on regular household 115V. A larger 220V version is also available. Costs about 650-700 bucks and takes out all the guesswork. Pick one up, go to the boneyard, pick up some old scrap and start practicing. Money well spent.
George, thanks for spending time with your kid in the shop. My old man was an alcoholic and never did anything with me. I had to learn everything myself, I screwed up my share of cars over the years. My neighbours were car guys and eventually showed me how to do things properly. Remember, build the car for YOU, not anybody else. If you sell it down the road you can decide if you want to tell the buyer about it. The only person you have to answer to is you. Shawn
The jb weld will hold up well, but the rusty metal underneath it will not. However if it was between using it to make a temp. fix or not being able to get the car on the road, I'd use the jb and drive the shit out of it. Just don't invest a lot of money in the paint job because it will need repair again in the future.
Thanks for the idea George G. I have a 27 coupe body with some pinholes on the topside of the cowl at the base of the A-pillars. This area has some compound curves in it that I'm not currently capable of duplicating in steel so I can't just cut them out and put new "panels" in. I also don't want to try and weld the holes shut since the steel is pretty thin. I'm a realist not a perfectionist and this patch method is ok by me in my situation. I don't think your post is intended to promote JB Weld as a panel adhesive but rather a pin-hole filler. That's the way I'm reading it anyway. Nothing cooler than a father working on a project with his kids. You rule.
I just had a couple things to say about using epoxy: Epoxy has a different expansion rate than steel. Every time the sandwich of steel and epoxy heats up and cools down, the steel expands at a different rate than the epoxy. That can eventually crack the epoxy. So it's a temporary fix in that respect. Filled epoxies only have about 2,500 to 4,000 pounds per square inch of tensile strength -- which sounds good until you know that steel has about 50,000 pounds per square inch of tensile strength. After that steel/epoxy sandwich gets flexed back and forth from normal driving vibrations, eventually the epoxy will be the one that cracks and fails. It'll show up first as hairline cracks in the paint covering the epoxy/steel seam and get worse. Also having a thicker (and stiffer) repair area next to thinner surrounding metal puts a stress riser where the thick area meets the thin area which can cause cracks at the edge of the repair area. Epoxy is pretty difficult to remove if you can't get to it easily. Some paint stripper type glop like JASCO that contains methylene chloride can eventually make it swell up and fall apart, but nothing really dissolves cured epoxy. Solvent doesn't dissolve epoxy. So it'll be a real pain for somebody to have to grind and chip away an epoxy repair job if it's sandwiched between two steel panels. It'll be difficult to get the steel clean enough to weld to even after getting most of the epoxy off too. Epoxy resin isn't really that great for sealing steel against corrosion. I have done experiments with it. I etched steel parts in acid down to shiny bare steel, carefully dried them, and encased them in a block of clear epoxy resin. A few months later, I could see rust forming on the steel looking through the epoxy. Epoxy primer paints like PPG DP-40 or DuPont epoxy primer seem to protect steel very well against corrosion, but epoxy resin doesn't seem to work as well for some reason. I suspect that the epoxy primer paints have something in them like acetone which draws the moisture up out of the pores of the steel to keep it from corroding, while epoxy resins just wet to the surface and trap moisture inside the pores of the metal. Who knows, but don't count on JB-Weld or any 2-part epoxy resin from protecting steel against corrosion forever. But that's cool that you and your son were having fun fixing that mess with each other. It might work okay for five years or so like the other guys have mentioned. If you want to keep doing repairs that way, it would probably be better to spray the steel panels with epoxy primer first for corrosion protection. Then use "panel adhesive" instead of J.B. Weld. I think some of the new panel adhesives are polyurethane based. They're probably designed to flex slightly, rather than be hard and brittle like J.B.Weld is. But they're not really meant to be used in exterior seams that will get painted. They're really meant for things like bonding hood skins to hood support structures. I guess it all depends on if you want to do it right, or do something that'll just last for five years. Welding would be the way to go though. If you get a welder, you and your son can have lots of fun learning how to weld together.
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