Foam stuffing of the frame to decrease rust and increase strength

If I lived in the rust belt, I would pull the frame after all my mods to it and get it hot dipped galvanized and never look back.
If it were brand new and in perfect shape. Problem is that every frame in the rust belt is in the rust belt, so there isn't anything that is perfect shape... Or not many. Your might find a handful of Sunday drivers, only driven to church jeeps to start with. Or "import" one from the desert SW. Honestly, I think if/when my frame goes, throttle down customs offers a hot dip galvanized option... It's spendy, but it's done once.
 
If I lived in the rust belt, I would pull the frame after all my mods to it and get it hot dipped galvanized and never look back.
Curious, could you setup a rolling frame without a tub?
 
If it were brand new and in perfect shape. Problem is that every frame in the rust belt is in the rust belt, so there isn't anything that is perfect shape... Or not many. Your might find a handful of Sunday drivers, only driven to church jeeps to start with. Or "import" one from the desert SW. Honestly, I think if/when my frame goes, throttle down customs offers a hot dip galvanized option... It's spendy, but it's done once.
I think that one has some quirks that you’d have to deal with.
 
If your frame is decent why would you need to strengthen it?
All foam closed cell and open has an "absorption rate" closed being not much absorption cant remember the %.
We use a two component closed cell for spongy fiberglass bottoms in boats and bathtubs. The issue the bond to the sides of the substrate. If water or moister finds it's way in it will just sit there and not dry then start to rust. With it being filled tou have no recourse to clean or inspect the frame.
I would think cleaning and applying a rust preventer like Fluid Film as much as it may suck is a better solution. Just my 2 cents.
 
after turkey season i plan on removing my bumpers , park it on my hillside and pressure washing the inside of the frame. then hit her with 1 or2 cans per rail with cor-ban with a 36in extension nozzle !
 
If I lived in the rust belt, I would pull the frame after all my mods to it and get it hot dipped galvanized and never look back.

Some time in the summer of 2019 I met a guy at a Jeep show that had taken his whole Jeep apart and sent his frame to somewhere his friend worked to get it galvanized. Somehow someone screwed up and he got it back a couple hundred lbs heavier because it was almost full. What did he do? He put it back together and never worried about it. Probably because it will never rust and he never takes it off road. Crazy but true story.
 
I think that one has some quirks that you’d have to deal with.
Yeah... But so does any rust free replacement frame I'd get now-a-days. It's most likely gonna be a wreck from down south, so you have squareness and crumple zones to deal with. I think @toximus had a good idea with just cutting the bad sections out and fish plating new material in.
 
Some time in the summer of 2019 I met a guy at a Jeep show that had taken his whole Jeep apart and sent his frame to somewhere his friend worked to get it galvanized. Somehow someone screwed up and he got it back a couple hundred lbs heavier because it was almost full. What did he do? He put it back together and never worried about it. Probably because it will never rust and he never takes it off road. Crazy but true story.
he should be glad they didn't screw up too bad. we had a guy once who put some 15ft long pieces of aluminum i-beam off a plane in the wrong chemical tank. when he took them out the only thing left was the fastener holes. :eek::eek::eek: he never lived that one down. took 3 weeks to get new parts machined and installed.
 
Yeah... But so does any rust free replacement frame I'd get now-a-days. It's most likely gonna be a wreck from down south, so you have squareness and crumple zones to deal with. I think @toximus had a good idea with just cutting the bad sections out and fish plating new material in.
I mean I think they use proprietary skids and things so some parts wouldn’t be reusable.
 
I galvanized mine. Best mod you can do for a tj I also drilled the body mount pieces off the bottom of the tub and had those dipped too and panel bonded them back on. I seam sealed the entire bottom of the tub while it was off. I would have rhino lined it but I only had a week to finish the work. Rust up here is terrible on vehicles and I have no plans of ever getting rid of my tj so it was worth it to me.

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Foam is not a sealant, it is a trap. Any shit that will get into the foam, or between the foam and metal will sit there and rot... which will eventually lead to exactly opposite.

Test data is there, entire Jeep section of craigslist from salt belt of the US continent, and winter roads of Eastern Europe.
...But as someone once said - not my circus, not my monkey.
I have not found any study with closed cell foam contributing to accelerated rust. It is used a good bit by industry, the new Jeeps use foam in the cab and roof to help sound proof, so if you own a monkey/new jeep may be worth studying. Pretty easy to test the idea with a couple of sections of frame. I will soak them in a salt water mix and measure with and without foam. Open cell foam would be a bad idea, but closed cell should seal the area just like paint products for undercoating.
 
I have not found any study with closed cell foam contributing to accelerated rust. It is used a good bit by industry, the new Jeeps use foam in the cab and roof to help sound proof, so if you own a monkey/new jeep may be worth studying. Pretty easy to test the idea with a couple of sections of frame. I will soak them in a salt water mix and measure with and without foam. Open cell foam would be a bad idea, but closed cell should seal the area just like paint products for undercoating.
You are in TJ section of the Jeeps, the 20 year old one, and not the one fresh off the factory.
Move to the salt belt, or where i am from.
In 10 years update me with your findings.
Till then, you are 1 microscopic gold nugget in the junk yard, trying to prove to me that the junk yard i am seeing is a gold mine.
 
It is used a good bit by industry, the new Jeeps use foam in the cab and roof to help sound proof

that may be, but keep in mind that the environment most manufactured products are exposed to are not the same as an automobile. I can't think of anything other than marine that spends half it's life with all it's nooks and crannies getting sprayed by salt solution day after day and is still around in 20 years - and the marine industry just expects to strip and recoat their steel periodically.

Even if the closed cell foam itself is perfect with 0% moisture pass-through, can you count on the bond between it and the inside of the frame to be perfect as well? There are a lot of holes in that frame and each one is an entrance.
 
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If I lived in the rust belt, I would pull the frame after all my mods to it and get it hot dipped galvanized and never look back.
This is the reason all of the Military frames are still trolling about in the caribbean and central america. Ask anyone about a Willys and they'll tell you about one, or point to one still working like a champ. Galvanizing correctly the frames should be something the factory uses regardless.

The foam idea isn't bad, it's the materials we have that limit the effectiveness long term. If we can get something that both repels water 100%, and also etches itself to the metal creating some type bond, we would not see the issue. Rust is iron reacting oxygen exposure with moisture as a catalyst. Without the continuous exposure to two of those, you can limit, or stop it.
 
I personally would not foam the frame. It will just hold more salt and sand. You would be better off using some long 360 degree nozzle hoses from SEM that will go onto a fluid film can or SEM rust fighter. You can reach inside the frame pretty well and in all the body holes. Also consider wire brushing and seam sealing the underbody. My floor and fenders rotted way before the frame did.
 
I forgot. Add some good size drain holes before and after the rear wheel arch. The early frames did not have them. My old frame was packed with sand and mud in those spots before I swapped it.