Rust, here I come!

[MarkWard]

Most primers don’t seal the surface. You should top coat the primer. I am a big fan of rust oleum rattle cans. Get the shop vac running near where you spray to catch overspray.

I have read that a Fein oscillating tool makes quick work of removing sealer from the seams. Ospho is a syringe to treat the seams. Have a damp rag to clean up the Ospho.
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☮️

[VicVan]

[VicVan]

Polyurethane seam sealer applied over the primer.

Tomorrow, rust paint.
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'90 Little Blue Truck, 2WD auto, FAS GenV 2.0 NA (AVH)

[Steve M.]

OSPHO is good because it flows like water so like water it gets into all the crevices which is the hidden rust.

My thinking on the bedliner is along the sames lines as one former members idea to encapsulate the body to prevent the Northeast road salts getting to the metal.
After properly treating the rust you could seal the whole area which would essentially make a water trough that would hold the water for evaporation if you had an airflow back there for condensation prevention. One of the Westys rust problems come from leaking plumbing and as been pointed out- the 3 ports on the side of the Westy.

I put the bedliner on my front bumper area to seal it from pooling water. The P.O. or his paint shop used bondo to cover the rusted area and that was how I first saw it by the rust pushing up the bondo in places. I removed all the bondo, sand blasted and OSPHO treated, primer painted, topcoated to seal the primer and then the bedliner.
My idea was to not use any bondo to hide the metal seam and I can see the seam outlined through the bedliner. Hopefully if I can keep tabs on it I might actually see problems as it develops. I have scheduled reminders on my Google calender to start checking it for years to come!

It is the first time I'm trying it so it is another experiment in progress.
And I did treat and seal the seam from the back side as well.
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This free advice is worth exactly what you paid for it.

There are seven days in a week. Someday is not one of them.

[Steve M.]

The rust always comes back.
Why?

As Mark pointed out you have to seal the primer. Primer is not waterproof and it probably holds moisture in it.

Bondo is not waterproof either. It may be water resistant to a good degree, but it will absorb moisture.
I know no body shop or anyone doing body work that seals the primer paint before putting Bondo over it to repair rusted or dented metal.
It's clean the rust-primer-bondo then topcoat it and take your money.

If it is a known rust area then moisture is getting in there somehow. If it is just water absorbing primer and bondo on the metal you know what is going to happen. You have to seal that primer the day you put it on even if you used a rust treating chemical. Then you can bondo the hell out of it if you want to.

The OSPHO and other rust chemical treatments change the rust and seal the surface. OSPHO creates a phosphate coating on the metal to seal the surface.
The other chemicals, do something similar.
The drawbacks to some of the chemicals is that the ones I'm thinking of are a thick white liquid you brush on - they do not flow like OSPHO so they are not going to get into the crevices.

What is perhaps ironic is that the application of OSPHO requires it to be rinsed with water as the final step.
_________________
This free advice is worth exactly what you paid for it.

There are seven days in a week. Someday is not one of them.

[jacklar]

I'm at the exact same stage as you but the hole I've got up front is a bit more gnarly. Foolishly I had the van painted recently but didn't pull the interior. Lesson learnt. That said thankfully I haven't found any other rust throughout.

At some point, I'll have this cut, welded and repainted. For now, I've pulled the insulation, added sound dampening mats, adding in some Closed Cell Foam.. wondering if I should add more insulation after that?

Vic, where'd you find ospho in Canada? I've got a POR-15 kit, wondering if that's similar enough or should I hunt down Ospho and mimic the exact same process?

Clean up rust, coat in Ospho, fiberglass/putty the hole, prime, top coat?

I'm getting this all prepped with the hopes we'll be able to venture to your side of the country later this summer.

[VanMan2009]

Ospho is just phosphoric acid, at about a 35-40% concentration. You can find it cheaper at Home Depot (or similar store in Canada) - "Klean Strip" I think it's called.

[RoryGirl]

[VicVan]

Hi Jack,

Similar rust indeed!
I've covered the hole with fiberglass, but I don't know if it's a good idea or not. I will eventually apply wax/coating in the cavity using the drain holes underneath, so I wanted to seal the area.
I know nothing about bodywork, I learn as I go, mainly from TheSamba and from local vendors (and also by experience...)

So yeah, I wire brushed, Osphoed, fiberglassed, primed, sealed, painted. I need to do the outside now (See pics on page 1)

Pic after paint (Thanks to Steve and Mark for reminding me to paint over the primer)

With the (overkill) insulation:

Finally starting to put it back together (new hoses and floorboards). Note that I've deleted the city water, I jus't can't think of a situation where I'd use that. I'll just put the sealed hook-up box back outside for now.

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'90 Little Blue Truck, 2WD auto, FAS GenV 2.0 NA (AVH)

[MayorMcCheese]

[VicVan]

Good idea on the lower side of the boxes, didn't think of that.
I also plan to take care of the rest of the insulation, one area at a time. By the way, is it possible to remove the cabinet in the rear, driver's side (the "wardrobe"), without removing the Air Conditioning unit?
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'90 Little Blue Truck, 2WD auto, FAS GenV 2.0 NA (AVH)

[nocreditnodebt]

Ospho, in my experience with several other phosphoric acid/ rust converter type products, is by far the best and worth the premium in my opinion.

I find the instructions to just apply twice and wait 24 hours, and remove the white flakes then paint to be a bit too 'marketable'

Here's what I do. The wirewheel for the loose stuff if no grease/ oil/ crud is present. If it is then a solvent and a good rag first to clean up as much of it as possible.

I like those wirewheels that can fit on a corded drill as opposed to an angle grinder, as one can spin the drill in reverse and find more to remove. Most battery powered drills spin a bit slow and their batteries are not intended for long times with little load and replacement batteries are insanely expensive.

The angle grinder wire wheel is of course faster, sometimes too much so.

I really enjoy slowing angle grinders/belt sanders via a router speed controller.

Once wirewheeled, I get a packet of dollar store sponges with the blue or green scrubbie on them. Granted this is no scotchbrite quality scrubbie, but it is good enough for this task. I take a sharp waxed chef's knife and cut off 90% of the sponge, and save it for later making my own paintbrushes.

With some quality gloves, Like Ansell 88-394 AlphaTec Chemical Resistant Gloves, wet the sponge with Ospho and just go over all the wirewheeled rust and adjacent paint. The only paint that gets damaged is that with rust already underneath it, so I dont worry about it hitting paint.

Once scrubbing is no longer seemingly effective, let it do the 24 hour thing, or if you are in a rush apply some heat.

Once the rust turns black, one can take a cheap but relatively sharp chisel and scrape the black off back to brown rust underneath, and also lift off the paint that the Ospho lifted from the rust that was hiding under the paint, then bust out the Ospho wetted scrubbie again while moving on to adjacent areas.


One can continue this procedure of chiselling then scrubbing off converted rust, until they get down to bare pitted steel, if they so wish.

I know that Naval jelly is supposed to do the same thing, but it never has in my attempts, and the whole 'rinse with water' in the instructions of Naval jelly, bother me tremendously.

I know the correct way to fix rust is to cut it all out and weld in new metal, I don't have access to proper metal fabrication tools such as a welder and a brake.

I do however have good fiberglassing skills and Epoxy resin, on properly prepped surfaces, has tremendous adhesion, many times that of 'fiberglass resin' which is just polyester sanding resin, whose adhesion is a joke in comparison to epoxy.

1 coat of epoxy painted on can be 10 times or more thicker than a single layer of paint, and be sandable in 4 hours. It bonds far stronger than paint, seals the substrate many times better, will expand and contract with the surrounding steel with heat or cold much much better than polyester resins ever dreamed of.

In places where one might think Bondo like consistency is a good call, I mix my Surfboard epoxy precisely, by weight, 100:45 in case of Apex epoxy, then thoroughly mix it within the mixing cup. Then I add milled glass fibers and some wood flour, which is sort of like the powder one gets from their belt sander sanding cedar with 150 grit.

When it is similar to peanut butter consistency I'll spread it like bondo over the surfaces already painted and uncured with unthickened epoxy. If the painted epoxy is still tacky and it is not too humid one can get a chemical bond. If the painted epoxy is allowed to cure then it has to be sanded for a good bond for any subsequent layer added.

Amine blush forms on epoxy, even the 'blush free' epoxies, and more so in the humid weather. It is water soluble, and can be scrubbed off, but subsequent layers require scuffing for 'mechanical tooth' for maximum bond strength.

it is better to be able to apply more epoxy atop epoxy that has not yet cured and formed that amine blush. The chemical bond is superior to a mechanical bond. I've often mixed three batches and applied two and 3 when one was still nowhere near tacky. Its a bit less stresssful than trying to do it all within the potlife of batch number one. and less work than waiting, removing blush and then sanding for layer 2.

The 'wet out table' method is a great way to lay in patches of fiberglass.

I get some new clean uncreased cardboard and raise and staple and tape the edges for form a dam and intend multiple uses from it. I cut out the size patches of fiberglass and several layers depending on cloth weight and desired strength/stiffness. and have all the patches set up and ready for wet out. Always make sure the weave of fiberglass cloth is perpindicular and parallel. Sharp new scissors are your friend. protect your lungs. cut rectangulars trying to stay in line. Oval patches are good too.

Apex Epoxy at 70f has about 25 minutes of working time if spread thin once thoroughly mixed.

So I mix the epoxy precisely by weight, and thoroughly in the cup making sure to scrape the sides and corner of the cup several times until a strong light and good reading glasses reveal no swirlees. I then wet out the fiberglass patches on the cardboard quickly and move on, to let it soak in and saturate.
I then take the foam or bristly paint brush and goto the Osphoed and cleaned formerly rusted metal and cover it all.

I then go back to the cardboard and squeegee the extra resin from the fiberglass patches and put it back in the mixing cup.

i then mix in the milled glass fibers and the wood flour and mix until iut is peanutbutter consistency and then spread it thin up the sides of the cup, or if I have another piece of cardboard that has already been saturated with epoxy spread it thin on that.

Epoxy in a mixing cup will get hot and thicken quickly and become unworkable. One spreads it thin to give themselves much more time to work with it. If one really wants to they can put it in the fridge to give themselves more working time. I've found a couple ice packs in the bottom of a larger cardboard box and the cardboard tray laid atop gives me all the time I need.

I then take the squeegee and lift the thickened epoxy and spread it over the rusted uneven areas filling any depressions/ pits. I then scrape the squeegee clean and lift the prewetted fiberglass patches from teh carboard and carefully position them over the epoxy already painted/squeegeed over the area.

Epoxy slowly gets thicker and thicker and at some point one needs to stop trying to work it.

Polyester resin reaches a point where it goes from workable to unworkable in about 20 seconds.

Epoxy does not stick to the plastic used in plastic baggies. Think the thicker plastic used in freezer lock bags. Epoxy does not solvent evaporate to cure so laying plastic over it will not stop it from curing. One can have pieces of this plastic cut out, and lay it over the layered epoxy/ fiberglass and use the squeegee or other tools, such as a gloved finger, to form it/flatten it, make nice radius in corners. With enough care one can make it so any subsequent sanding is unnecessary, though corners are always problematic.

If the metal surfaces one applies the epoxy to are properly prepared, the adhesion is very impressive. If the fiberglass patches are fully wetted and laid on thick, I've drilled and tapped it for machine fasteners.

The Apex Epoxy is among the cheapest available, and hardly one of the best, but is miles better than regular two part or 5 minute epoxies in the adhesion and impermability departments.

Don't be afraid to put Ospho in a cleaned spray bottle. I've stuck the nozzle inside places That I knew are rusty, but which I could never reach without cutting. Even if the Ospho is not painted it certainly slows the continuation of the rust, especially if the area is kept dry from that point forward.

With good gloves like the Ansells, and a scrubbie soaked in Ospho, cleaning and prepping the rusted areas is almost cathartic, especially if one has the time to come back in 20+ hours and repeat the process. If one is in a rush the rust might turn black in much less time and one just attacks the black with the chisel and scrubs it with more Ospho and more grey steel is revealed as less and less black remains.

Epoxy, is not UV stable. It needs to be painted over with actual paint, if exposed to sunlight. I no longer put primer or Paint directly on metal. I paint the treated metal instead with epoxy, and then paint that. If fiberglass and thickened epoxy are needed too, so be it.

Some people cant tolerate the Epoxy hardener, others can become sensitized to i over time with additional exposure. It can be cleaned off skin, or tools with Distilled white vinegar. Never use acetone if it is on your skin. The dust is bad until it is fully cured, then it is inert. Full cure can take a while under 70f and efforts should be made to insure it does not drop below a certain temperature for the first 8 hours, I think Apex is 60f but other epoxies will have a minimum temperature to not let the workpiece fall below.

While it does still eem to cure when things heat up the next day, it is far better to not let it fall below that minimum temperature during that first 4 to 8 hours or whatever the specific epoxy says. Ambient temps play a role, so if you have 3 hours of 65f+ and want 7 hours, have a method for increasing the temp or wait until the next day and get on it early.

It can't be stressed enough that the epoxy MUST be mixed to its precise ratio either by volume, or by weight. Its hard to mix small batches by volume even if one finds good mixing cups into which to do so. A digital scale is something I kick myself often for not having acquired much much sooner.

If one screws up the ratio, by 5 to 15% the epoxy will not adhere as strong as it otherwise would and not be as strong as it otherwise could though it will still seem to be hard and will sand.

One gets about a 3% margin for error, if that, It is NOT like polyester resin where the catalyst affects the cure time and too little just takes longer.

When mixing by weight, I'll still mix to the 0.01 of a gram.

If the epoxy says 100:45 by weight, I will pour hardener to the mixing cup on the 0'd scale. When done pouring that number I put it into the calculator adn multiply it by 0.45. I then hit the tare button then carefully pout that much hardener. One drop is anywhere from 0.03 grams to 0.06 depending on temperature. Its easy to go over. The hardener is lighter and mostly stays on top. Pouring in the middle of the cup and I will lift out excess on the mixing stick until I get it to 0.01 of a gram, though many say 0.1 of a gram is more than close enough.

If one really screws up the ratio or the mixing then the uncured never to cure epoxy is a totally toxic nightmare to deal with. It is a curst fest to end each and every cursefest that ever came before, or any curse fest ever to occur in the future.

If one cant or wont take the precise nature of Epoxy.....mixing parts A and B seriously, and then insuring parts A and B are thoroughly mixed within the cup, then do not bother. It will be a complete waste of time/materials/effort unless cursing for hours on end is something you enjoy.

Make sure the mixing stick fits the bottom corner of the cup as this will reduce the time it takes to thoroughly mix it within the cup and give more working time. Make sure you scrape all 5 sides of the mixing stick on the edge of the mixing cup, and mix those scrapings into the bottom until one can identify no swirlees under a strong light. If one spills an amount down the sides of the mixing cup, especially early in the mixing, then just start over.

its good to have something that needs a good glue or some sealing, when there is extra epoxy mixed or if the ratio is not perfect enough to risk on the main task.
If a batch is compromised it might be more than good enough for another task, but not for adhering to properly prepped substrates where bond strength and durability and cured strength are paramount.

https://fiberglasssource.com/collections/epoxy-resin

While I use this Apex Epoxy, there are certainly better epoxies available. System 3 clearcoat epoxy is a very slow curing epoxy and is super thin. I've had it adhere to waxed glass so strongly that it could not be removed, whereas the Apex epoxy lifted off with a razor without much struggle at all.

The 'Epoxy bondo' that I make with wood flour and lilled glass fibers does not easily sand, but its adhesion and impermability to moisture and air is so far above regular bondo that I Never use bondo for anything anymore, not anything I care about anyway.

There are other thixotropic agents one can use instead when sanding ease is desirable, but they likely compromise impermeability

https://www.systemthree.com/blogs/epoxy-files/83509508-about-the-system-three-epoxy-book

When the final stage is a Paint that needs to look good, then any contamination of the surface before laying down the final coat of epoxy should be negated, or 'fisheyes' will form. These areas repel the epoxy and will 'orange peel' and it seems like the very bottom of the depression where that contaminant was which repelled the epoxy, remains on subsequent attempts to fill those depressions.

Apex epoxy seems pretty bad in the fisheye department. Some of The surfboard guys swear by resin research Additive F, which is rumored to be Xylene and some parrafin wax to act as a surfacing agent, which prevents the fisheyes.
Some of them just say prevent the contamination and keep the evil xylene away from your shop.

I was unaware of fisheyes, until I switch from expensive System3 epoxies to cheapo Apex.

[MayorMcCheese]

[nemobuscaptain]

[nemobuscaptain]

[ghianowbug]

Help me understand why leave the bottoms of the hookups unsealed. You are trying to prevent water from infiltrating.Stop the water from coming in . I would seal all four sides as you are keeping the water out not making a vent for humidty. Leaving the bottom open would get more water in than can escape by leaving it unsealed . Just think about wasing your car. The side of the vehicle will have water spraying up while driving. so once the water is dripping through the gap it settles on the bottom. Someone mentioned vapour barrier that is the way we build in canada have the vapour barrier on the warm side . This will keep moist air from the inside from getting into the cavity and condensing against the metal panel. In a camper you always have sources of moisture stsrting with the occupants and if you have propane stove that adds best to make sure that you ventilate the van so that it drys out after use.

[ghianowbug]

Now that you seam sealed the inside you are pot committed to fixing the outside otherwise the water will come through the seam cracks from outside and sit under the seam sealer leading to the same problem again . I agree that you should seal the rust or the primer my choice would have been a rust encapulator paint . The one I use is the eastwood. If there any other areas like this do the same thing to both sides simultaneously as now if you work the seam from the outside and use the acid then cant rinse well or dry well acid may stay in the seam and if you rinse with water may be a problem . acid under the paint leads to failures. For the outside seam i would stick to mechanical rust removal and though you dislike it media blast as it would get into the seam well. Someone said use baking soda good for paint shiite for rust . As you think glass blasting is dirty wait till you see the soda cloud. Stay with the glass . Then use an encapsulor to coat then top coat . This way no acid and still get rust protection .

[VicVan]

Thanks Ghia for the suggestion. I don't mind blasting with glass again since I'm on the outside now... As for the acid, it's already there anyways. The Ospho I had applied on the inside slowly crept all the way to the outer seam. So the harm is done, and the rust already converted.
Here's what I think I'll do:
- Mask off/protect area
- Pick at and remove existing seam sealer (it's crumbling already, the ospho creeping from the inside was the coup de grâce)
- Media blast, moderately
- a little bit of Oshpo
- Primer
- Seam sealer
- Paint (I'll order a custom-made spray can at a local paint-shop)


This picture was taken as some of the Ospho had already made its way through, see areas in gray:

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'90 Little Blue Truck, 2WD auto, FAS GenV 2.0 NA (AVH)

[ghianowbug]

If you wish to use acid then make sure you rinse well. The fast etch that I use says that you can rinse with water or use acetone to wash away tge excess acid . This way u rinse without introducing water by use acetone.

I would still go for the mechanical removal so you do not introduce more acid. Acid that can seep under the seam sealer inside.

[ghianowbug]

by the way you said some of the seam already converted that is fine just wipe of the excess acid and neutralize the rest so you dont have paint problems after .