Rusted Roof

[Pete]

Originally Posted by bigriver

I've started the process of prepping to Monsterliner the pop top and roof. This is what I found under my corner rub tape. When the metal is pocked like this can I still mitigate further rusting without having it cut out and new metal welded in? If so any suggestions how to proceed appreciated. I've read this entire thread but still the question remains.

I think you need to cut that metal out and weld in new to avoid everything rusting underneath the lining.

[posplayr]

Originally Posted by oceansrealm

I have tried rhino liner and all sorts of paints on my repairs and have found that the most robust solution so far has been repairs with bondo an/or fiberglass then a generous coating of flex seal.

I agree

I have been using the fiberglass-reinforced Bondo for some time now. It is fully waterproof and very much a structural covering.

If one is extremely ana;l and has the skills, then go for it and weld in some sections of sheet metal. But if you properly treat the rusted areas, you can fully fill the drip rail and cover most any rust problems.

Even if you do need to tack weld some metal into an extremely rusted situation, it is going to be far easier to make it presentable with the Bondo.

https://www.amazon.com/762-Bondo-Hai...17306426&psc=1

https://www.amazon.com/Bondo-00277-G.../dp/B00PB3NTFO

So this Bondo is not as strong as a full expoxy glass layup but it doesn't need to be and it certainly will be much easer to final form.

As I read this thread I don't think people understand that what is causing the rusting is the dirt getting down into the OEM drip rail sealer. The water is washing it in there, but once the dirt gets it it is amazing how much it rusts even in a dry CA/AZ climate.

[bigriver]

After further research I've decided to use the three step POR 15 approach and put the paint matched Monstaliner on top of that... unless someone has a good reason not to that is

[E-350]

Not sure if you saw the other thread from larrie where sheepshagger mentioned adhesion of paint on POR-15 isn‘t that good.

As also mentioned I used 3 layers epoxy primer + 3 layers bedliner on my bare metal roof/ gutter.

[bigriver]

Thanks E-350. I had read sheepshagger's comment but then went down the rabbit hole and came out thinking it could be done. Now revisiting the POR 15 info in more depth, and considering his comment, I'm thinking a good rust converter and primer instead. I'm not planning on filling or I would use posplayr's Bondo Glass approach. We'll see how it all plays out next week.

[SheepShagger]

Originally Posted by bigriver

Thanks E-350. I had read sheepshagger's comment but then went down the rabbit hole and came out thinking it could be done. Now revisiting the POR 15 info in more depth, and considering his comment, I'm thinking a good rust converter and primer instead. I'm not planning on filling or I would use posplayr's Bondo Glass approach. We'll see how it all plays out next week.

That is a way better approach, and will also be 1/4 of the price. If you need verification, read paint forums on POR 15 in the application you are thinking. It’s a great product, just not for this specific application.

Personally I like OEM quality or better, hence recommend welding in a plate, but that’s requires tools, glass and bondo is an easier option, but make sure you read up on glass then bondo, vs glass reinforced bondo that’s designed for fiberglass boats and cars, like corvette.

[SheepShagger]

The other thing that was mentioned in the other thread (or this thread) sorry I can’t remember. Is that the ford seam sealer shrinks over time and creates a gap between the roof and the sealer, water and dirt gets into this gap and creates the rust problem. That is 100% accurate.
But what I have also seen people recommend is remove the seam sealer and simply paint. If you do that, you need to remember the joint between the roof / cutter / side is NOT waterproof, it’s spot welded. So you are now relying on the paint to create the waterproof barrier. IMO that’s not a good idea long term, that’s why I personally recommend using a quality seam sealer to replace the ford sealer if you see / have that crack. That’s also the reason ford used seam sealer in the first place in that gutter, to create a waterproof barrier.

[larrie]

I finished the three step Por-15 process today. Very time consuming due to the wait times between the steps. Tomorrow will be laying down the recommended Por-15 high build primer before applying the Herculiner.